LONDON (Reuters) - British Prime Minister Gordon Brown will miss a nuclear summit hosted by President Barack Obama in Washington next week as he campaigns for Britain's May 6 parliamentary election, his spokesman said on Tuesday.
Brown has asked Foreign Secretary David Miliband to represent him at the April 12-13 nuclear security summit, Brown's spokesman said.
"He will go with the prime minister's full authority," he said.
Brown earlier launched a month-long election campaign likely to be dominated by the economy and shaping up as the most unpredictable contest since 1992.
The opposition Conservatives are ahead of Brown's Labor Party in the opinion polls.
Brown is expected to discuss the nuclear summit, Afghanistan and possibly Iran in a regular phone call with Obama later on Tuesday, Brown's spokesman said.
Chinese President Hu Jintao is among world leaders who will attend the Washington summit, which will focus on securing nuclear material to prevent it falling into the wrong hands.
The Obama administration unveiled a new policy on Tuesday restricting U.S. use of nuclear weapons but warned Iran and North Korea that they remain potential targets.
(Reporting by Adrian Croft; Editing by Jon Boyle)