Pakistan's Cabinet on Sunday formally decided to launch legal action against former premier Imran Khan over his audio leaks in which he could allegedly be heard discussing the controversial US cypher and how to exploit it to portray his ouster in April as a conspiracy, according to a media report.

Taking notice of the leaks, the Cabinet on September 30 formed a committee over the audios on September 30.

The committee on Saturday recommended legal action over the audio leaks purportedly featuring Khan and others.

This is a matter of national security, which has serious implications for national interests and a legal action in this regard is vital, recommended the Cabinet committee.

The Cabinet approved the summary through circulation on Sunday, the Geo News reported.

The Federal Investigation Agency will be given the task to probe into the US cypher and the audios.

In the two audio leaks, Khan, ex-minister Asad Umar, and then-principle secretary Azam Khan could allegedly be heard discussing the US cypher in a meeting and how to use it in their interest.

In the first audio that was leaked on Wednesday, Khan was reportedly talking to Azam and directing him to play with the cypher.

In the second audio clip, three Pakistan Tehreek-e-Insaf (PTI) party leaders, including Umar, Shah Mahmood Qureshi and Azam could be heard talking about the American cypher with Khan, the party's chairman.

US Assistant Secretary of State for Central and South Asia Donald Lu is the central figure in Khan's claims about a US-backed regime-change conspiracy.

Khan accused Lu of threatening Pakistan's former ambassador to the US, Asad Majeed, that a failure to remove Khan through a no-confidence vote would herald consequences for Pakistan and vice versa.

Khan was ousted from power in April after losing a no-confidence vote in his leadership, which he alleged was part of a US-led conspiracy targeting him because of his independent foreign policy decisions on Russia, China and Afghanistan.

Khan used the cypher to portray his downfall in April as a conspiracy by the US and widely use this narrative in public rallies. He also calls the current government imported.

The 69-year-old cricketer-turned-politician is the only Pakistani Prime Minister to be ousted in a no-confidence vote in Parliament.

The US has denied any role in his ouster.

Meanwhile, Pakistan Muslim League-Nawaz (PML-N) leader Maryam Nawaz Sharif on Saturday expressed her discontent with the government led by Prime Minister She h baz Sharif over its failure to arrest Khan despite a litany of charges that merited his detention.

She asked the government to carry out a raid at Khan's Bani Gala residence to recover the stolen copy of the cypher.

Finance Minister Ishaq Dar said that Khan was power hungry and wanted to rule the country at any cost.

The decision is that the matter will be taken forward under the Official Secret Act," he said.