July 31 (Reuters) - Canada's WestJet said on Friday it has begun parking Boeing 737 planes as negotiations with flight attendants have not resulted in an agreement, which could lead to labor disruptions.

Cabin crew at the Calgary-based carrier, owned by Onex Corp ( ONEXF ), could strike as early as August 2 at 12:01 a.m. Mountain Time (0601 GMT), if talks fail to produce an agreement over a dispute on unpaid work, the Canadian Union of Public Employees, which represents WestJet flight attendants, had said on Thursday.

The union is asking for cabin crew to be paid from the time they check in to when they clock out, which is not the case currently.

"We remain active at the bargaining table to achieve a mutually agreeable deal at the earliest possible time," WestJet said in a statement on Friday, adding that parking the aircraft allows it to maintain operational control.

WestJet Encore flights  operated  on Bombardier's Q400 and codeshare flights operated by partners remain unaffected, it said.

The Canadian Union of Public Employees did not immediately respond to a Reuters request for comment.