Liberal Democrat MP Layla Moran has said a member of her family has died in Gaza.
The Oxford West and Abingdon MP, whose mother is Palestinian, told the Commons her family member died due to their inability to access medical care.
She was speaking ahead of a vote on a motion calling for a ceasefire in the Israel-Gaza war.
Ms Moran said it was the "most difficult day" she had endured in her parliamentary career.
"We are now over a month on from the atrocious attacks by Hamas on 7 October, and we were all right to utterly condemn the attacks," she told the House of Commons.
"But ahead of the votes that we are going to take in a moment I wanted to let the House know that today I lost my first family member.
"The reason why this is important, having spoken about how they are in a church in Gaza City and how they didn't, I am afraid, die of a bomb - instead they died perhaps for lack of food, perhaps for dehydration.
"Their health deteriorated in the last week and they couldn't get to the hospital they needed."
The MP has previously spoken about being "deeply worried" for her extended family in Gaza, with some sheltering in a church, unable to move south, after an Israeli missile struck their home.
Ms Moran became the UK's first MP of Palestinian descent when she was elected in 2017, and is the foreign affairs spokesperson for the Liberal Democrats.
She told the Commons she was backing calls for a ceasefire.
"Today, I wanted to vote for peace. I wanted to be voting for a two-state solution, because that is the only way that these horrors will never be seen again," she said.
"I wanted to vote for getting Hamas out of Gaza, and I wanted to vote for those reasons for an immediate bilateral ceasefire, so that families like mine - but also families in Israel - don't have to endure this anymore."
She added that it was "more than just party politics right now".
Last month, Ms Moran told the BBC's Victoria Derbyshire: "No longer are people saying, where do we go to be safe?
"The question they are now asking is, where do we want to be when we die?"
At least 1,200 Israelis were killed in the Hamas attacks on 7 October, when gunmen infiltrated communities near the Gaza Strip. More than 200 hostages were snatched at gunpoint.
In retaliation Israel launched a war against Hamas - proscribed as a terrorist organisation by many Western governments, including the UK.
Since then, more than 11,000 people have been killed in Gaza - 4,500 of them children - according to the Hamas-run health ministry.
Forty-six Israeli soldiers have been killed in the fighting inside Gaza over the same period, the Israel Defense Forces say.