On 5 April 2009, he succeeded Anders Fogh Rasmussen as prime minister following the latter's appointment as Secretary General of NATO.

[1] He subsequently formed the Moderates, which campaigned on ending bloc politics, and won 16 seats in the 2022 Danish general election.

[7] Rasmussen's campaign was supported by the party youth branch, and raised 600,000 DKK which were spent on school equipment[7] in Soviet occupied Afghanistan.

[8] The photos have generated a lot of media attention in Denmark, after the Danish participation in the war in Afghanistan and especially as Rasmussen moved up the rankings at Venstre.

Since 2002, the government has awarded extra funds earmarked at reducing the waiting list at National Health Service hospitals, a grant sometimes referred to by the media as Løkkeposen[9] (A pun on 'lykkepose' the Danish word for a goodie bag).

[11] As Finance Minister Lars Løkke Rasmussen led the negotiations concerning funds to banks affected by the 2007–2008 financial crisis.

As deputy of the largest party in the government, Lars Løkke Rasmussen thus took over the post as Prime Minister of Denmark.

[15] An opinion poll released on the day of Lars Løkke Rasmussen's takeover revealed that Danes believed that he only beat Helle Thorning-Schmidt as the person best suited for bringing Denmark through the 2007–2008 financial crisis, and that Thorning-Schmidt would have been better suited to combatting unemployment, reducing hospital waiting lists, securing the welfare society of the future, and representing Denmark internationally.

At the first meeting of the summit high level section, led by Lars Løkke Rasmussen, a number of countries protested the Danish handling of the negotiations.

The World awaits us”, said Lars Løkke Rasmussen responding to criticism of the Danish led negotiations coming from several countries who regarded them as undemocratic.

The BBC's climate correspondent stated: "According to all my sources, the Prime Minister's Office is on the verge of a melt-down.

He remained in office as head of a caretaker government until his successor, Helle Thorning-Schmidt, was appointed on 3 October 2011.

His Blue Bloc won a tight election in which his party came third overall, winning Rasmussen the ability to form a government.

In 2015, Rasmussen denied US Senator Bernie Sanders's characterization of Denmark as socialist, noting that the nation had a market economy.

With the result beyond doubt on election night, Rasmussen conceded defeat to the "red bloc" under the Social Democrats' Mette Frederiksen.

[29] Following lengthy government negotiations, he was appointed minister of foreign affairs in Mette Frederiksen's second cabinet.

[30] In July 2024, he attended the 2024 NATO Summit in Washington, D.C., where he met with Israeli Foreign Minister Israel Katz.

[31] Løkke Rasmussen and his Nordic counterparts signed a joint letter in late October 2024 condemning Israel's planned bill that would seek to ban the UNRWA from operating in the country and in effect the Palestinian areas.

In the spring of 2008, he was accused by the media - essentially the Danish tabloid Ekstra Bladet - of having charged his official accounts with considerable expenses he should have paid himself, e.g. restaurants, cigarettes, taxis, and hotels, both as county mayor[33] and as minister.

[36][37] In May 2007, Rasmussen was again accused by Ekstra Bladet of having his ministry pay for a hotel room in Copenhagen when he privately attended a Paul McCartney concert in Horsens in 2004.

[41][42][43][44][45][46][47][48][49] In 2013, the Global Green Growth Institute (GGGI) was criticized by two member countries for its financial management: Norway withheld $10 million in donations, citing excessive spending on flights and food by GGGI former Council Chairman Lars Løkke Rasmussen, and both Norway and Denmark demanded an Audit of the organization's finances before renewing support for 2014.

The case resulted in criticism as Rasmussen's presence, as then-Prime Minister, could be perceived as inappropriate pressure on the school leader; for meetings of this sort, it is usually the union representative that functions as the civil assessor.

"[52][53] Just as Rasmussen refused to apologise, so too did following prime ministers of Denmark, and Helle Thorning-Schmidt declined to participate in an investigation.