The APA Teamsters Local 1224 union has hit back at Atlas Air Worldwide (AAWW) after the lessor filed a lawsuit accusing members of an "illegal work slowdown".

The union accused Atlas of using the lawsuit to "pass blame" and "distract customers' attention from operational failings".

The teamsters went on to reiterate concerns over an intensifying staffing crisis that it said is driving operational challenges at the company.

The response comes after Atlas Air and Polar Air Cargo Worldwide - both part of AAWW - accused unions of an "illegal work slowdown" and filed a complaint with a US district court to stop the action.

The company’s request for a preliminary injunction was filed in US District Court for the District of Columbia.

An initial status conference on the lawsuit was held on September 29 before the US District Court for the District of Columbia. The judge has scheduled the case for trial on October 31 in Washington DC.

The lawsuit comes as the two parties are currently in negotiations over a new contract for pilots. The company is hoping to unite its pilots under one contract, following its acquisition of Southern Air and Florida West International Airways last year.

The unions claim that AAWW wants to merge Atlas and Polar's contracts into Southern Air pilots’ existing contract which, they said would cut wages and degrade working conditions for Atlas Air and Polar Air Cargo pilots