LONDON (Reuters) – British Airways said it would fly more than 60 percent of passengers with flights booked for this weekend despite a three-day cabin crew strike that risks hurting the Labour government weeks before an election.

The walkout over pay and jobs will disrupt travel for thousands after talks between the Unite union and management collapsed.

A BA flight to Tel Aviv late on Friday was the last to leave London’s Heathrow before the action formally started at midnight. A further four-day strike is planned later this month.

Prime Minister Gordon Brown called for both sides to resolve their differences without delay, as political opponents sought to capitalize from Unite’s position as his party’s biggest single financial backer. The prospect of the first national rail strike for 16 years added to the government’s problems after signal workers voted for industrial action on Friday, although peace talks were due to be held next week.

Labour has strong union ties that go back to its foundation in 1900. The political director of Unite, Britain’s largest union, is Brown’s former spokesman. The opposition Conservatives, favorites to win an election expected on May 6, called on Brown to sever financial links with the union during the dispute.

‘’Labour’s dependence on funding from Unite is compromising their ability to stand up to the unions and stand up for the interests of passengers,’’ Conservative transport spokeswoman Theresa Villiers said.

BA, which has 12,000 cabin crew, wants to save an annual 62.5 million pounds ($95 million) to help cope with a fall in demand, volatile fuel prices and increased competition from low-cost carriers. BA Chief Executive Willie Walsh apologised for the disruption to passengers in a video on the carrier’s website.