He said protecting time to spend with his son and daughter made him more relaxed and a better decision-maker.
Sir Keir and his wife Victoria have a 16-year-old son and a 13 year-old daughter.
He told Virgin Radio: âWeâve had a strategy in place and weâll try to keep to it, which is to carve out really protected time for the kids, so on a Friday â Iâve been doing this for years â I will not do a work-related thing after six oâclock, pretty well come what may.
âThere are a few exceptions, but thatâs what we do.â
Labour leader Sir Keir Starmer with his wife Victoria at the state banquet for the Japanese emperor (Aaron Chown/PA)
He said his son and daughter are his âpride and joyâ and âI donât want to lose that timeâ.
He added: âI donât believe in the theory that you are a better decision-maker if you donât allow yourself the space to be a dad and to have time for your kids.
âActually, it helps me, it takes me away from the pressure, it relaxes me, and I think, actually, not only is it what I want to do as a dad, it is better.â
In politics âsome people think, if you fill your diary 24/7 and donât do anything else, that makes you a much better decision-makerâ.
âI donât agree with that, I think youâve got to make space, so we do it. â
In an interview with Chris Evans, who used to play football with the Labour leader, Sir Keir suggested his children appeared unimpressed with his political career.
After winning a Spectator politician of the year award, he said his son asked âhow did you blag that, then?â.
And when he was speaking at a fundraising dinner his daughter asked: âWhy would anyone pay to hear you speak?â
âThey keep me very, very grounded,â Sir Keir said.
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