Cameron: "His party is a wholly owned subsidiary of the Unite union"
David Cameron has called Gordon Brown's efforts to stop a planned strike by BA staff "feeble" as the two men clashed in Parliament over the issue.
The Tory leader said the prime minister had shown no "backbone" because of Labour's links to the Unite union, whose members are backing the walkout.
But Mr Brown said the Conservatives were more interested in "provoking" the airline dispute than resolving it.
He added he had spoken to both sides and hoped they could reach a deal.
Since the strike was called last week, the Conservatives have sought to exploit Labour's links with Unite - the union is Labour's largest donor - and the relationship between its officials and Downing Street.
During heated exchanges at prime minister's questions, Mr Cameron said Mr Brown's approach to the strike - which is due to begin this weekend - had been "weak".
He asked the prime minister to support British Airways staff who were prepared to cross picket lines to "help get this business going".
"It is back to the 1970s," he said. "We have got handwringing from a weak prime minister while companies go down."
Mr Cameron said the prime minister was reluctant to intervene in the dispute because of Labour's financial links to Unite, describing the party as a "wholly owned subsidiary of the union".
What passengers are wanting to know, what the country is wanting to know is whether we can resolve this dispute
"They pick the candidates, they choose the policies, they elect the leader and they have special access to Downing Street. This why his response is so feeble. Isn't is true that when the crunch comes he can only act in the union interest not the national interest?"
Mr Brown, who has previously described the strike as "deplorable", said the Conservatives should be "ashamed" of themselves for using the dispute as a "political football".
"I have already made my views clear about this dispute. What I also know is what passengers are wanting to know, what the country is wanting to know is whether we can resolve this dispute," he said.
"He [Mr Cameron] has said nothing positive about resolving this dispute. It is the same old Tories."
Mr Brown said he had spoken to both management and unions and believed that the two sides could "build" on an earlier outline agreement to resolve the dispute before the strike action began.
Lib Dem leader Nick Clegg said both main parties were being "bankrolled", comparing Labour's links to Unite with the Tories' relationship with its deputy chairman and donor Lord Ashcroft.
The party's home affairs spokesman, Chris Huhne, told the World At One that Labour's financial links with Unite cast doubt on whether it could act as an "honest broker" in the BA dispute.
"When general secretaries of Unite decide to snap their fingers, cabinet ministers do tend to come to attention," he said.
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