A leaked diplomatic cipher recently published by a U.S.-based media outlet led to an uproar in Pakistan, as it revealed U.S. involvement in the ousting of then-Prime Minister Imran Khan last year.

Outgoing Prime Minister Shehbaz Sharif said on Thursday that if the alleged contents of the cipher published by the U.S.-based The Intercept publication on Wednesday are "true," it amounts to a "massive crime."

Pakistan Tehreek-e-Insaf (PTI), the party of incarcerated Khan, on the other hand, reiterated its demand for an investigation into the cipher sent by the country's former Ambassador to Washington Asad Majeed, last year, which Khan had cited as "proof" of a conspiracy to topple his government.

Khan was deposed by a vote of no confidence in Parliament on April 9, 2022.

The Intercept published what it said is leaked content from the cipher, which included an account of a meeting between U.S. Assistant Secretary of State for the Bureau of South and Central Asian Affairs Donald Lu and then-Pakistani Ambassador Asad Majeed.

"Details of the secret document (cipher) have once again endorsed the stand of Imran Khan that the no-trust move against his Constitutional and democratically-elected government was brought under a conspiracy," said the PTI in a statement.

Following his meeting with Lu, the Pakistani diplomat sent the cipher to the Foreign Ministry in Islamabad.

According to the full transcript of the cipher published by the news website, Lu mentioned the no-confidence motion.

The ambassador wrote to Islamabad: "He (Donald Lu) said that ‘I think if the no-confidence vote against the Prime Minister (Imran Khan) succeeds, all will be forgiven in Washington because the Russia visit is being looked at as a decision by the Prime Minister. Otherwise, I think it will be tough going ahead.’"

Then-Prime Minister Khan visited Moscow in February 2022 and met with President Vladimir Putin on the day Russia declared war on Ukraine.

The PTI chief blamed Washington and his then-Army Chief Gen. Qamar Javed Bajwa for the collapse of his coalition government.

However, both Washington and his successor government in Islamabad have repeatedly denied the accusation.

'Washington objected to Khan’s foreign policy'

According to the cipher's purported contents, Washington objected to Khan's foreign policy regarding the Ukraine war.

"Don (Donald Lu) referred to Pakistan’s position on the Ukraine crisis and said that ‘people here and in Europe are quite concerned about why Pakistan is taking such an aggressively neutral position if such a position is even possible. It does not seem such a neutral stand to us.’ He shared that in his discussions with the NSC, ‘it seems quite clear that this is the prime minister’s policy,’" read the cipher excerpt.

In response, the ambassador said this was not a correct reading of the situation as Pakistan’s position on Ukraine was the "result of intense interagency consultations."

Sharif, however, said the former Pakistani ambassador to the U.S., "clearly" told a National Security Council (NSC) meeting that "there was no discussion of a conspiracy in his meeting with Donald Lu."

"Imran Niazi said that this conspiracy was hatched because of his growing relations with Russia ... but my government purchased cheap oil from Russia," he added.

Last year, Pakistan's successive governments, first led by Khan and then by Sharif, held two NSC meetings to discuss the cipher. The NSC noted that there was external interference in Pakistan.

Following his meeting with Lu, the ambassador added a note of assessment in his cipher to the Foreign Office in Islamabad: "Don (Donald Lu) could not have conveyed such a strong demarche without the express approval of the White House, to which he referred repeatedly. Clearly, Don spoke out of turn on Pakistan’s internal political process. We need to seriously reflect on this and consider making an appropriate demarche to the U.S. Cd’ A a.i (charge d'affaires) in Islamabad," The Intercept reported.

Islamabad later summoned the then-U.S. diplomat in Pakistan to lodge the protest.

Anadolu Agency (AA) was unable to independently verify the contents of the cipher revealed by The Intercept.

The publication claimed the cipher was provided to it "by an anonymous source in the Pakistani military who said that they had no ties to Imran Khan or Khan’s party."