Former cabinet minister Sir Ed Davey has ruled himself out of the race to be the next Liberal Democrat leader.
The ex-energy secretary said he had taken the decision with his family in mind and amid concerns about the “inevitable intrusion” that a leadership bid would entail.
Former business secretary Sir Vince Cable is so far the only candidate to throw his hat into the ring.
Norman Lamb is among prominent figures to have ruled themselves out.
Former Scottish secretary Alistair Carmichael has also declined to stand while Jo Swinson, who was seen as a frontrunner, was recently elected as deputy leader.
Candidates from among the party’s 12 MPs who want to succeed Tim Farron have until 20 July to declare.
In a statement on the Lib Dem Voice website, Mr Davey – who served in the cabinet between 2012 and 2015 and who returned to Parliament at the election after losing his seat two years ago – said the decision not to run had been a difficult one.
But he said he had to put the needs of his family and his two children – one of whom is severely disabled – ahead of his political ambitions for the time being.
“Being there for my children over the next few crucial years and to see those special moments is my personal priority,” he wrote.
“So my decision not to stand now to be leader of our party is a difficult one, but it is rooted in my family.
“The need to be there for my young children and not continually away from home; the need to protect my family from the inevitable intrusion on our lives; and the need to protect myself from pressures that would otherwise compromise my job as a father while they are still so young.”
The 51-year old said he wanted to play a “big part” in continuing to rebuild the party, which he said must focus on telling the public what it was for rather than what it was against.
“If I’d run, my message would have been simple: we need to be the party of reform, challenging the status quo. Saying the uncomfortable things. Recognising how broken our politics is,” he wrote.
Sir Vince, now the clear favourite to become leader, tweeted in response: “Very much admire & respect what my friend and colleague has said today about the importance of family.”
Tim Farron is standing down this summer saying he could no longer reconcile being a committed Christian with being the leader of a progressive political party.