The candidate nominate [sic][clarification needed] in accordance with the provisions of the foregoing paragraph shall submit to the Congress of Deputies the political programme of the Government that he intends to form and shall seek the confidence of the Houses.3.

The outgoing government had been a PSOE minority cabinet with the external support of Unidas Podemos—the electoral alliance of Pablo Iglesias's Podemos, United Left (IU), En Comú Podem, Equo and other minor left-wing parties—as well as case-by-case support from the smaller regional and nationalist parties; after the election such a scheme could count with the 165 seats garnered by both PSOE and Unidas Podemos, but was hampered by the former's reluctance to reach any deal with Republican Left of Catalonia (ERC), which, together with Together for Catalonia (JxCat), had triggered the April 2019 election by siding with right-of-centre parties to reject Sánchez's 2019 General State Budget.

[2][3] Both Cs and PP leader Pablo Casado—who described his party's dismal performance as "very bad" but rejected to resign from his post—vyed for the leadership of the opposition to Sánchez's government, with far-right Vox having entered parliament for the first time.

As a result of the election, the Spanish right was fragmented into three slices which, even taking regional allies such as Navarrese People's Union (UPN)—running within the Navarra Suma alliance—into account, could only muster 149 seats, far from any prospective shot at forming a government.

[11] It was commented that Sánchez expected for a new government to be up and running by 20 June, but acknowledged that negotiations and the investiture vote itself would be delayed as a result of the ongoing campaign for the 26 May local, regional and European Parliament elections.

[18] While the incorporation of Podemos into the government had been generally seen as feasible after the 7 May Sánchez–Iglesias meeting, Iglesias acknowledged that his negotiating position had been weakened by his party's results in the local, regional and European Parliament elections, but insisted on his demand for entering the cabinet nonetheless.

[20][21] Following the 26 May elections, King Felipe VI held a round of talks with the various parties with parliamentary representation in the Congress of Deputies which saw Pedro Sánchez being formally nominated as prime ministerial candidate on 6 June, which he accepted.

[27] On 11 June, Sánchez met again with the leaders of PP, Cs and Unidas Podemos, this time in the building of the Congress of Deputies, in a move that signaled the formal start of negotiations 43 days after the general election.

"[31] A new and discreet Sánchez–Iglesias summit on 17 June saw no advances or specific commitments, but rather "generic exchanges", an offer by the PSOE to award Unidas Podemos "intermediate posts" in the government structure outside the Council of Ministers—which was rejected by the latter—and the finding that the two parties' positions were "very far apart" because of the way in which each group understood the "cooperation".

[36] Finance minister María Jesús Montero warned Podemos that there would not be new opportunities should Sánchez's investiture—scheduled for July—fail, hinting at the possibility of a snap election being needed to unlock the situation, though this heavy-handed tone was brought down by the government the next day.

[40] The next day, Sánchez offered Iglesias to designate a number of "renowned independents" to be appointed as ministers,[41][42] and on 8 July the PSOE appointed a negotiating team to address programmatic contents with Unidas Podemos on the basis of a document synthesizying the key elements of the Socialist electoral manifesto: employment and pensions; feminism and fight against social inequality; climate emergency and ecological transition; technological advance and digital transition; and Spain's position in Europe.

[45] On 11 July, Sánchez offered Unidas Podemos the right of appointing cabinet ministers on the condition that they had a "technical profile", which was regarded by Iglesias as a "veto" to the main leaders of his alliance—including himself—and the proposal was rejected.

[55] Initially, negotiation talks went smoothly, with both parties being confident and optimistic on 21 July of an agreement being reached by the time of Sánchez's second investiture voting within four days, in which only a simple majority—that could be achieved with the support of Unidas Podemos, Compromís and the PRC and the abstention of ERC—would be needed for success.

[56][57][58] With promising advances on programmatic contents, the issue still remained on what Podemos's position in the cabinet would be, with the PSOE stressing its dominance of the so-called "state ministries" (Foreign Affairs, Justice, Defense and Interior) and disputes on the Finance, Labour, Social Security and Ecological Transition portfolios.

[67][68] Negotiations resumed in the 48 hours between the first and second rounds of voting, with both parties making offers amid a climate of distrust: Podemos' offer was leaked by the PSOE to the media, and it included demands for a post of deputy prime minister and five ministries (Social Rights, Equality and Economy for the Citizens; Labour, Social Security and Fight against Precariousness; Ecological Transition, Environment and Animal Rights; Tax Justice and Fight against Fraud; and Science, Innovation, Universities and Digital Economy).

[77][78] On 26 July, the King chose to postpone any new round of talks "for the time being", refusing to appoint anyone to form a government until political parties were able to reach an agreement for a successful investiture.

[85] On 20 August, Unidas Podemos sent a new document to the PSOE, proposing "to resume dialogue" and "form a coalition government as soon as possible" after the "shortage of time" prevented an agreement in July.

[87][88][89] Both parties met again on 5 September, but no agreement point was found: Podemos' spokeswoman Ione Belarra claimed that "the PSOE maintains its immovable position", whereas its Socialist counterpart Adriana Lastra stated that "we have confirmed our differences".

[99][100] On 23 September, with the deadline for government formation having been reached, the 13th Legislature of Spain came to a close and the Cortes Generales were dissolved by the King the following day, with the election date being set for 10 November 2019.

[101] The November 2019 election resulted in both PSOE and Unidas Podemos losing ground—falling from a combined 165 seats to 155—in a more fragmented parliament, with both PP and Vox emerging stronger at the expense of Citizens' collapse in support (which led to Albert Rivera's resignation as party leader).

Concurrently, ERC asked its members whether it should block Sánchez's investiture "if a negotiation table is not agreed upon first to address the political conflict with the State", in order to raise pressure and increase the price of its consent to a PSOE government.

[141] The PSOE also secured the support of Más País, Compromís, the BNG, NC and the Teruel-based Teruel Existe platform, as well as the abstention of CCa, whereas the PRC announced that it would vote against Sánchez's investiture in protest to its agreement with ERC.

[147][148] One day earlier, the Central Electoral Commission (JEC) decided on 3 January both to strip Catalan president Quim Torra of his status as regional MP—enforcing a judicial ruling in December convicting him for disobedience, after he refusing to remove a poster in favor of imprisoned Catalan independence leaders from the balcony of the Palau de la Generalitat during the May 26 local elections campaign—and to reject accepting ERC leader Oriol Junqueras's appointment as a MEP.

[152] Further complications arose when CCa deputy Ana Oramas chose to disobey her party and vote against the investiture—instead of abstaining—accusing Sánchez of "kneeling before secessionism" and dubbing his investiture agreements as "an offense against the rest of the [autonomous] communities".

[159][160] Teruel Existe MP Tomás Guitarte denounced a series of threats and a massive spamming campaign on his e-mail demanding him not to support Sánchez,[161][162] to the point that the interior ministry was forced to ensure his protection ahead of the vote.

[157] Only two months into Sánchez's new term in office, in March 2020, the newly-formed government had to face the outbreak of the COVID-19 pandemic and its impact which, included the COVID-19 recession resulting from the extensive COVID-19 lockdowns implemented to curb the spread of the SARS-CoV-2 virus.

[168] Later, the government would have to face the economic impact of the Russian invasion of Ukraine in 2022, as well as growing tensions between both coalition partners—including a succession in the leadership of the Unidas Podemos alliance from Pablo Iglesias to Yolanda Díaz following the former's departure in March 2021—and the troublesome political relationship with pro-independence parties ERC and EH Bildu.