Jack Straw told a constituency meeting in Blackburn he'd been "astonishingly blessed" to represent the town and work as minister and shadow minister but that at 67 he "couldn't guarantee" he could keep up the pace required into his mid-70's.
Althoughhe backed his brother David in the Labour leadership campaign in 2010, Mr Strawpaid tribute to Ed Miliband:
"In Ed Miliband we havea leader who has the ability, the determination, and thecharacter to take this country to a better, and much fairerplace than under this Government."
More top news
Detectives investigating the Parsons Green terrorist attack have arrested a 17-year-old boy in Thornton Heath, south London.
Speaking to ITV News Foreign Office minister Tobias Ellwood said education was the greatest weapon in the fight against extremism.
A review of the law is being considered after a cyclist who crashed into and killed a mother-of-two was convicted using a Victorian law.