Political turmoil: Former US NSA holds telephonic conversation with Imran Khan

• Bolton says "instability and violence are not in anyone's interests."
• Former adviser tweets against trial of protesters in military courts.
• Raises concerns over Imran Khan's treatment.

Former national security adviser (NSA) to United States ex-president Donald Trump, John Bolton, has spoken with Pakistan Tehreek-e-Insaf Chairman Imran Khan as the country passes through a political crisis.

Senior PTI US leader Atif Khan confirmed the development on Friday.

"Former UN Ambassador under Bush Administration and National Security Advisor under Trump Administration John Bolton had a phone call with Chairman Imran Khan today," Khan tweeted without elaborating further.

Bolton, earlier this week, had expressed concerns over the "continued instability" in the country triggered by the arrest of Imran Khan on May 9.

The former adviser, while taking to his Twitter, wrote about the critical interests of the US in Pakistan.

“The US has critical interests in Pakistan. Continued instability and violence are not in anyone's interests. The treatment of Pakistan's former premier Imran Khan hinders relations and raises tensions,” he tweeted.

The American politician went on to speak against the civilians being tried in military courts.

“Civilians should not be tried in military courts where they have no access to basic rights,” he tweeted.

Former US diplomat Zalmay Khalilzad has also been critical of the Pakistani government's crackdown on PTI. He said the instability in the country could weaken the entire region and trigger war.

"I am concerned about the deepening triple crisis in Pakistan: economic, political and security. Pakistan is becoming unstable, poorer, and less secure," he said in an interview.

Khalilzad's comments come after over 60 US lawmakers, in a letter on Thursday, asked Secretary of State Antony Blinken to exert pressure on the Pakistani government in order to address the human rights situation in the country.

The letter was written after the efforts of the Pakistani-American Political Action Committee (PAKPAC).

The letter, coauthored by Congresswoman Elissa Slotkin and Congressman Brian Fitzpatrick, was signed by 65 other lawmakers "who are deeply troubled by the democratic backsliding and human rights abuses in Pakistan".