Dame Margaret Beckett, the first woman to serve as foreign secretary, has announced her intention to retire at the next general election, some 48 years after first becoming an MP.

Labour leader Sir Keir Starmer hailed Dame Margaret, who was also the first woman to lead the party, as a “trailblazer” after she said she plans to stand down from the Derby South constituency.

First elected in Lincoln in 1974, she served as acting leader of the Labour Party in 1994 after the sudden death of John Smith.

That year she ran for election to lead the party full time, but lost to Tony Blair, who would later make her foreign secretary.

Derby Labour Party announced that the 79-year-old politician would not seek re-election at the next national vote in 2024.

In an interview, Dame Margaret discussed the sexism she faced in the Foreign Office as a holder of one of the great offices of state in the 1990s.

“I regarded that as their problem rather than mine,” she told BBC Radio 4’s Today programme: “There were people in the Foreign Office I understand who thought that.

While she temporarily led the party, Labour members have never elected a woman as their leader, unlike the Tories who have done so twice.

“There’s so much luck in politics,” Dame Margaret said.

“It was just never the right person at the right time.”

Two MPs have been killed within the last six years, and the perceived threat to them and the abuse they face is all too extreme.

Asked if she would advise children today to go into politics, Dame Margaret said: “It wouldn’t put me off because what I felt when I was considering being an MP is equally true today.

“If you think things should be changed, and you want to have a say in changing them, and you don’t have wealth and power, there’s a very limited number of routes you can use and this is the biggest of them.”

She acknowledged the huge challenge Sir Keir has if he is to win the next election after Jeremy Corbyn’s defeat, but said the public can “move mountains” in the British electoral system if they wish.

Deputy Labour leader Angela Rayner said: “So many years of dedication to public service and to better politics.

“What a woman and what an inspiration Margaret is to us all.”

Sir Keir paid tribute to the “legend of our party”.

“As the UK’s first female foreign secretary, and Labour’s first female leader, she is a trailblazer,” he said.

“Margaret, I thank you for everything you’ve given, and achieved.”