Ms Kelly says she wants to spend more time with her children
Transport Secretary Ruth Kelly is to stand down as an MP at the next general election.
She made the announcement at a Labour supporters' meeting in her Bolton West constituency.
Ms Kelly made it clear she wanted to spend more time with her four children as they grew up, and stressed she was not seeking a safer seat.
She has already said she will leave the cabinet at the next reshuffle - expected on Friday.
Ms Kelly said it had been an "honour and privilege" to serve the constituency since she became an MP in May 1997.
"I've thoroughly enjoyed serving the people of my constituency and intend to continue to keep working diligently for them until the next general election," she said.
"I've taken the area to my heart and will leave with a touch of sadness and fond memories, although I'm sure the decision I have taken is right for myself and my family."
She said she was confident Labour was well placed to deal with the current financial turmoil "under the strong leadership of Gordon Brown".
Ms Kelly added: "I look forward to campaigning actively for Labour and firmly believe that we can win Bolton West at the next general election.
"Only a Labour Bolton West MP working with a Labour government will build in the years to come on the solid foundations we've already laid."
Ms Kelly, who has four children aged 11 or under, won Bolton West at the last election, in 2005, with a 2,064-vote majority.
Councillor Cliff Morris, chairman of the Bolton West constituency Labour Party, paid tribute to the MP.
"I've known Ruth from the start of her time as a Bolton West MP and it's been a pleasure to work with her," he said.
"I'd like to thank her for all the hard work and effort she's made for the people of her constituency during the last 11 years."
Ms Kelly became education secretary in 2004, before becoming communities secretary and then moving to Transport in 2007.
Prior to her resignation as a minister, there had been speculation the 40-year-old, a devout Catholic, could leave the government because of her objections to the Human Fertilisation and Embryology Bill.
After her decision to leave the government was revealed, Prime Minister Gordon Brown said: "There are no political issues between Ruth and me."
Ms Kelly described the prime minister as a "towering figure".