The resignation of Anneliese Dodds as international development minister "won't make a difference" to Sir Keir Starmer, Harriet Harman has said.
The Labour peer told Beth Rigby on Sky News' Electoral Dysfunction podcast that there is "such coherence" in the rest of the cabinet that her decision to quit will do little damage.
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Ms Dodds resigned on Friday over the prime minister's announcement to slash the overseas aid budget to fund an increase in defence spending.
Baroness Harman said it is "very characteristic" of the outgoing minister, "who is a thoroughly principled and decent, loyal person".
She added: "I think that the truth is that there is such coherence in the cabinet, and Keir Starmer's political management of the cabinet is so absolutely functional and strong that, although I don't want to take away from Annaliese on this, actually it won't make any difference to that."
It was put to her that the resignation will create bad headlines after Sir Keir's successful trip to Washington to meet Donald Trump.
Baroness Harman conceded that "there'll be a lot of sadness amongst Labour MPs", and that she personally would have liked to have seen Ms Dodds "try to refocus what is left of the development agenda" and "keep alive the arguments for the pathway back to 0.7% [GDP spending on foreign aid]".
She said: "There is a hard reality, which is that money needed to be found and it needed to be found really quickly, because when it became clear towards the end of the weekend that actually the defence spending had to go up on a timescale, and therefore there would need to be switch spending that would need to be announced on Tuesday, this became the only option."
Former leader of the Scottish Tories Ruth Davidson was a bit more frank about the departure, saying the cut to the aid budget put Ms Dodds in a "completely uncredible" position as she would have struggled to maintain relationships with organisations the foreign office was working with.
She added that Sir Keir already sacked her as shadow chancellor in the early days of his leadership and then as party chairman after the election.
"She ran this amazing election campaign, they had this amazing majority. He fired her the very next day and made her a junior minister, and then he gutted her budget," said Ms Davidson.
"She had nowhere else to go."
In her resignation letter to the prime minister, Ms Dodds acknowledged there was "no easy path" to fund the boost to defence but claimed there had been a "tactical decision" for the Overseas Development Aid (ODA) budget to "absorb the entire burden".
Sir Keir announced the decision to cut the aid budget on Tuesday, saying it would fund and increase defence spending from 2.3% of GDP to 2.5% in 2027.
The prime minister admitted the inauguration of Mr Trump - who has made clear he no longer wants to bankroll NATO's defence - "accelerated" his decision but said it had been three years in the making, after Russia's invasion of Ukraine.
It means around £6bn per year will be taken out of the aid budget and transferred over to pay for defence.
That amounts to a reduction in aid spending from 0.5% of GDP to 0.3%.
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(c) Sky News 2025: Resignation of Anneliese Dodds 'won't make a difference' to Sir Keir Starmer, says Harriet Harma