Britain's industry mediator has put forward confidential proposals to try to end a long-running dispute between British Airways and its cabin crew.

Cabin crew have staged a series of five-day strikes in a dispute that has cost the airline around 150 million pounds ($218.5 million) so far. The Unite union said this week that it would ballot members on further industrial action.

Peter Harwood, chief conciliator with the Acas mediation service, confirmed that he had presented his proposals to the two sides following talks with the TUC union umbrella group.

I am expecting to meet the parties again early next week but given past events I hope everyone understands that the timing of the meeting and its location will be kept secret, Harwood said in a statement.

One meeting between the union and BA ended in chaos last month when left-wing demonstrators burst into the venue.

The strikes stem from BA's decision last November to cut cabin crew pay and alter staffing levels on its flights to try to save 62.5 million pounds a year in costs.

With the cost savings dispute largely resolved, the issue of travel allowances for cabin crew has become the main sticking point in the conflict.