UPDATE 1-UK's Brown says U.S. plan rejection disappointing

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LONDON, Sept 29 (Reuters) - U.S. lawmakers' rejection of a $700 billion financial bailout plan was "very disappointing", British Prime Minister Gordon Brown said on Monday.

The U.S. House of Representatives earlier voted against the plan to help the financial industry in a shock vote that sent global markets sliding.

"The vote in America is very disappointing," Brown told BBC television.

"We've obviously sent a message to the White House about the importance that we attach to taking decisive action in America."

Brown said he, Bank of England Governor Mervyn King and finance minister Alistair Darling would "take whatever action is necessary to ensure the continued stability of the system."

Earlier on Monday, Brown's government nationalised Bradford & Bingley BB.L, the second British bank taken into public ownership this year as a deepening financial crisis claimed victims around the world.

Brown threw his support behind the U.S. bailout plan when he held talks with U.S. President George W. Bush in Washington last Friday.

Bush said after that meeting he had told Brown the plan was big enough to make a difference and he believed it would pass.

The leader of Britain's opposition Conservatives, David Cameron, reacted to the U.S. vote by saying the "eyes of the world are on Congress."

"A deal is needed in order to stabilise financial markets and financial institutions, not just in America but elsewhere," he told reporters.

He said the Conservatives were ready to help the British government "in any way that is necessary to help bring stability at what is a time of great anxiety." (Reporting by Adrian Croft; Editing by Mark Trevelyan)