LONDON (AP) - British Prime Minister Gordon Brown waded into the acrimonious dispute between British Airways plc. and its cabin crew yesterday, calling a planned strike "deplorable" and risking a major fallout with key union backers ahead of a general election.

Brown's rare direct intervention in an industrial matter comes with the ruling Labour Party currently lagging in the polls behind the main opposition Conservative Party ahead of an election that must be held by June 3. The most likely date is considered to be May 6.

The walkouts scheduled by the Unite union for a total of seven days in the run-up to the busy Easter holidays are expected to affect hundreds of thousands of travelers.

There are also fears of wider industrial unrest after thousands of rail workers voted in favor of strike action that their union has said will likely target the Easter long weekend.

"It is the wrong time, it is unjustified, it is deplorable, we shouldn't have a strike," Brown told BBC radio of the BA walkout. "It is not in the company's interest, it is not in the workers' interest and it is certainly not in the national interest."

Brown's public hardline stance against Unite, one of the Labour Party's major donors, comes after he reportedly spoke with the union's leaders over the weekend.

The union is enraged at the intervention, calling Brown's Transport Minister Andrew Adonis "badly informed" after he too spoke out against the walkout and insisted it had been prepared to call off the walkout yesterday if BA had reinstated an offer it pulled last week.

The Conservatives, meanwhile, were swift to denounce Brown as hypocritical, saying he should cut Labour's links with the union.

"Gordon Brown cannot have it both ways," said George Osborne, the party's economy spokesman. "He can't condemn the strike whilst at the same time taking money from the strikers' union."

The Labour party was founded by the union movement, but donations aside, the unions hold less power now than in the 1970s when they took part in regular policy meetings with the government.

The planned BA strike is the latest move in a long-running dispute between Unite's 12,000 cabin crew members and BA management over a pay freeze and changes to working conditions.

A planned walkout over the Christmas and New Year break was canceled on court orders because of technical irregularities in Unite's ballot of its members.

Negotiations since then to try to find a resolution have failed amid accusations from Unite of intimidation and charges from BA that the union is trying to bring the airline to its knees.

The carrier has been particularly hard hit by the global economic recession because of its heavy running costs and reliance on increasingly unpopular first and business-class fares.

It argues that the disputed changes - including a pay freeze in 2010, a switch to part-time work for 3,000 staff and a reduction in cabin crew sizes from 15 to 14 on long-haul flights from Heathrow airport - are critical for its survival.

A report from the Civil Aviation Authority released yesterday underscored the problem, showing that British airports handled 7.4 percent fewer passengers last year than in 2008, the biggest annual decline since records began 65 years ago.

Unite argues it was not properly consulted on the changes and called on BA to reinstate an offer that was under discussion last week. BA pulled that offer after the union announced the strike dates - three days from March 20 and four days from March 27 - and said it would not recommend the offer to its workers.

"This company has never been prepared to negotiate seriously," said Unite joint leader Tony Woodley. "They are looking for a war."

BA chief executive Willie Walsh has said he remains available for talks 24 hours a day, but stressed that he planned to focus on looking after the airline's customers.

BA has been training around 1,000 workers who volunteered from other departments at the airline to stand in for cabin crew in the event of a walkout. Unite has attacked that decision, saying it will put BA's passengers' at risk in emergency situations.

The airline said Monday that it plans to operate more than 60 percent of its long-haul services into and out of London Heathrow over the first strike period. It will operate 30 percent of its short-haul services from Heathrow by using a combination of its own services and hiring up to 20 aircraft with pilots and crew.

From Gatwick, it will operate all long-haul flights and more than half its short-haul network. Flights from London City, including its New York route, will all operate as usual.

The airline has also agreed with 40 other carriers to rebook passengers on canceled flights free of charge.

"We are deeply sorry that our customers are the innocent victims of this cynical attack on their travel plans by the leaders of Unite," Walsh said in a statement, advising passengers to check the BA website regularly.

The airline said it would update passengers on plans for the second strike period after the first strike period has ended.

Unite stuck by a pledge not to hold a strike over the busy Easter period, after the planned Christmas walkout resulted in a public backlash against workers. But Unite assistant general secretary Len McCluskey said further action would take place after April 14 if the dispute is not resolved.

The RMT rail union, which represents some 10,000 rail workers around the country, revealed last week that maintenance workers had voted in favor of a walkout. It has not yet announced strike dates, but RMT leader Bob Crow warned passengers not to make travel arrangements over Easter.

"The fact this strike is due to occur at roughly the same time as the Network Rail dispute looks suspiciously like co-ordinated union action," said Norman Baker, transport spokesman for the opposition Liberal Democrat Party.

"The unions are trying their best to wind the clock back to the 1970s," he added, referring to Britain's infamous "Winter of Discontent" in 1978-1979 when thousands of striking workers crippled essential services across the country - and led to the election of Conservative leader Margaret Thatcher.