(Reuters) - A key aide of former Pakistani Prime Minister Imran Khan said on Wednesday he was quitting politics, dealing a further blow to the embattled ex-premier's party as a standoff with the military intensified.

Former Information Minister Fawad Chaudhry's resignation is the latest - and highest profile - in a string of departures from Khan's Pakistan Tehreek-e-Insaf (PTI) party, which the civilian government on Wednesday threatened to ban.

"I have decided to take a break from politics, therefore, I have resigned from party position and parting ways from Imran Khan," Chaudhry said in a post on Twitter.

The former information minister spent days in detention after violent protests swept the country this month after the detention of Khan on corruption charges.

Chaudhry condemned the protests by Khan's supporters, who attacked military installations, including army headquarters, and government buildings.

Khan says the corruption allegations were fabricated and that his associates are being forced out under duress from the government and the military in a manoeuvre to dismantle his party before elections scheduled later this year.

He has been embroiled in a tussle with the military since he was removed from power last year in a parliamentary vote which he says was orchestrated by the country's top generals. The military denies this.

Khan is Pakistan's most popular leader according to local polls, while the military is its most powerful institution, having ruled directly or overseen governments throughout Pakistan's 75-year history.

The face-off has raised new fears about the stability of the nuclear-armed South Asian country of 220 million people as it struggles with its worst economic crisis in decades.

Chaudhry is the second former federal minister to leave Khan. On Tuesday, former Human Rights Minister Shireen Mazari announced she was leaving politics, citing health concerns, after spending 12 days in detention.

Most of the top leaders of the PTI have been taken into custody. A number of former parliamentarians and mid-tier leaders have quit the party or politics entirely over the last few days.

Another key aide, former Finance Minister Asad Umar also announced on Wednesday, hours after he was released from detention, that he was resigning from his party position of secretary general.