The latest wave of strikes by British Airways cabin crew is drawing to a close with little sign of an early breakthrough in a bitter row over jobs and cost-cutting.
Members of Unite are taking industrial action for the fourth day in a row after an earlier three-day walkout, with warnings of further stoppages if the deadlock is not broken.
The two sides remained entrenched, trading fresh claims about the impact of the action.
Unite said it plans to raise £700,000 to support striking British Airways cabin crew with an "unprecedented" levy on its branches.
Officials said the move shows the union's resolve in continuing the dispute. A proposal for a mandatory 2% levy for the next quarter to support the BA strikers was approved by the union's executive.
Joint leader Tony Woodley said the move would raise £700,000, which will go on strike pay and other ways of supporting union members involved in the dispute.
He said: "This is an unprecedented move and it shows that Unite is absolutely determined to give our members all the support they deserve in winning this battle against the BA bullies. We continue to search for a decent settlement in this dispute but cabin crew are not going to be driven back to work for lack of resources."
BA said its contingency plans for the second period of industrial action had been "very successful".
BA chief executive Willie Walsh went to Gatwick Airport on Monday and thanked staff and passengers, adding: "We will continue to keep British Airways flying in the face of this unjustified industrial action."
Unite has said no action will be taken over Easter or before April 14, giving a window of opportunity for fresh talks after the strike ends.