[citation needed] Mohammad Natsir was sworn officially on 7 September 1950 at Yogyakarta Palace by President Sukarno as The First Prime Ministry of Indonesia.

On 22 January 1951, the parliament delivered a vote of no confidence and won, which resulted in Prime Minister Natsir to return his mandate to the President on 21 March 1951.

In order to not violated the congress decision too much, Natsir was deactivated from his position as the general chairman of Masyumi Party and was replaced by Jusuf Wibisono.

Despite having the trust and support of the Indonesian Parliament (DPR), the Natsir Cabinet was unable to carry out its program properly.

Parliament, chaired by Sartono from the PNI at the time, acted more as an opponent than as a government partner in planning and implementing cabinet programs.

They possessed weapons legally because they seized them from the Japanese and Dutch colonial forces who were then used to fight to defend Indonesian independence.

There are followers of S. M. Kartosuwiryo who called himself DI / TII in West Java, there was a communist group called "Merapi-Merbabu Complex" (MMC) In Central Java, there were Kahar Muzakar followers in South Sulawesi and "Laskar Hari Liar" in North Sumatra.

Soumokil who proclaimed the Republic of South Maluku (RMS) in Ambon on 25 April 1950, namely the RIS Cabinet (Mohammad Hatta).

The RIS government has tried to persuade the RMS by sending Dr. Johannes Leimena, a republican from Ambon to negotiate, but failed.

On 14 July 1950, RIS sent TNI troops led by Lieutenant Colonel Slamet Riyadi to quell him.

On 11 November 1950, TNI troops succeeded in occupying Fort Veronica which was the basis of the RMS defence and could subsequently take full control of Ambon City.

The big problem that must be resolved by Natsir while serving as Prime Minister was the demand for full autonomy for the Aceh region.

Subsequently, on 27 November 1950, the Vice President, Mohammad Hatta, came to Aceh to convey his views on regional autonomy in the DPRD building, but his speech was strongly opposed so he had to return to Jakarta the next day because he did not get results.

However, Natsir could not immediately come to Aceh because his second child, who was 13 years old, Abu Hanifah, had an accident while playing in the Manggarai Swimming Pool until he died.

For this reason, an in-depth study of all aspects, both weaknesses and strengths, is needed so that development can produce results.

Natsir's Cabinet assigned to a research company from the United States, J.C. White Engineering Corp to conduct a feasibility study for the formation of the National Design Bureau (BPN).

The Natsir Cabinet sent a delegation led by the Minister of Foreign Affairs, Mohammad Roem to a conference on West Irian which was held in The Hague on 4 December 1950.

Before the surrender was made, a conference was first held in order to preserve various Dutch interests in West Irian.

Noting that there was no intention of the Dutch to surrender sovereignty of West Irian to Indonesia, Prime Minister Natsir stated before the Indonesian parliament that the status of the Dutch-Indonesian Union needed a review.