Cabin crew were on strike again today for the third day of a four-day walk-out / PA

Unite is to raise £700,000 to support striking British Airways cabin crew with an "unprecedented" levy on members, the union decided today.

Officials said the move showed the union's resolve in continuing the bitter row over jobs and cost-cutting, which has cost the airline millions of pounds.

Cabin crew were on strike again today for the third day of a four-day walk-out following a three-day stoppage last week, which BA said has cost it around £50 million.

Unite maintained that BA's losses as a result of the disruption to flights and cost of hiring planes from other companies was nearer £100 million.

A proposal for a mandatory 2% levy for the next quarter to support the BA strikers was approved by the union's general executive, sources said.

Joint leader Tony Woodley said the move was "unprecedented" and would raise £700,000, which will go on strike pay and other ways of supporting union members involved in the dispute.

Meanwhile, the two sides continued to clash over the impact of the strike, with Unite insisting that growing numbers were joining the walk-out.

Union officials said 168 cabin crew reported for duty today, 33 were off sick and 196 on strike, adding that 140 BA flights out of 286 were cancelled at Heathrow's Terminal 3 and 5 this morning and a further 117 out of 203 will be cancelled later today.

The union claimed that only 42% of the airline's services were leaving Heathrow, most of them involving aircraft leased from other companies.

"BA's service today is severely impacted by the strike," said an official.

BA said: "At Heathrow, our flying programme is significantly more extensive than during the first strike period. We are operating 70% of our normal long-haul programme (compared with 60% last weekend) and up to 55% of our short-haul programme (compared with 30%).

"Due to the higher numbers of crew reporting for work than during the first strike period, we have been able to operate our expanded schedule at Heathrow with less than half the number of chartered aircraft used in the first strike period."