Straw, 67, has been a legislator in Britain's House of Commons for 34 years and also served as home secretary and justice secretary. But he is probably best known for his role as foreign secretary between 2001 and 2006 in the Labour government of Prime Minister Tony Blair and for backing the leader's decision to go to war in Iraq.
Britain's next general election is expected to take place in May 2015, beyond which Straw said he would not serve as a member of parliament.
He told constituents in the northwestern town of Blackburn that he decided to stand down after a great deal of thought and consultation.
"Labour is part of my soul, and so is this town," he told constituents, insisting that his "love affair" with Blackburn will not end after the next general election.
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Labour leader Ed Miliband said Straw will be "sorely missed" in the Commons, praising his service as foreign secretary in the aftermath of the Sept. 11, 2011, terrorist attacks in the United States, and his loyalty and support to the party.
After becoming foreign secretary in 2001, Straw staunchly backed Blair's decision join the US-led invasion of Iraq, a decision that was unpopular with many Britons.
Straw later said it was one of the most difficult choices he had ever faced and that he recognized the invasion had made many people "very angry." His role in that chapter of British history has made him a frequent target of anti-war activists.