Pakistan Tehreek-i-Insaf (PTI) Chairman Imran Khan on Wednesday requested the National Accountability Bureau (NAB) for time to appear before it in a case pertaining to alleged misuse of the Khyber Pakhtunkhwa (KP) government's helicopters during his party's tenure in the province.

NAB had initiated an inquiry against Khan in February for allegedly using two government helicopters — MI-17 and Ecureuil — for private visits and failing to pay their costs.

According to a NAB report, Khan should have paid the KP government Rs11.1 million, but official documents only mention payments worth Rs2.1m. PTI has rejected the allegations.

Khan was supposed to appear before a NAB investigation team today to respond to a questionnaire prepared by the body, but he instead sent a letter to the team through his lawyer Babar Awan saying that being the "head of the largest political party", he was busy in a nation-wide election campaign and, therefore, could not appear before the team.

He asked the anti-corruption watchdog to grant him "appropriate time... to join the proceedings".

According to the spokesperson of NAB's KP chapter, Salma Begum, the letter was sent to NAB Headquarters from where a formal approval or rejection to the request will be issued.

On Tuesday, Awan had asked NAB to set the hearing of the case on August 8, saying that the PTI chief is busy campaigning for the upcoming general elections and cannot appear before the body.