Bell Ribeiro-Addy said the government was likely refusing to say sorry because it feared it would make them liable for compensation - something Sir Keir Starmer has ruled out.

Although no amount of money can "fully reconcile for the horrors of enslavement and colonialism", she said "we do have to do things to try and move forward".

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Ms Ribeiro-Addy told Sky News: "I think the reason why they're not apologising is perhaps because of the liability, but a lack of an apology speaks to an absolute lack of respect.

"If we consider these countries our equals, we would apologise to them."

Downing Street said on Thursday that an apology for the UK's role in the transatlantic slave trade was "not on the agenda".

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The row has resurfaced at the Commonwealth summit being held in Samoa, where the King and the prime minister are in attendance.

Sky News has learned that leaders will agree plans to look at reparations at a heads of government meeting beginning today.

Sir Keir has called the transatlantic slave trade "abhorrent" but ruled out reparations as he said countries affected would rather the UK help them with current issues, such as the impact of climate change.

Ms Ribeiro-Addy, chair of the All-Party Parliamentary Group on Afrikan Reparations, said "at the very least we should be having a discussion" about compensation and that not willing to entertain it "may come across as quite disrespectful".

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She said most countries calling for reparations "are unable to meet today's challenges when we haven't completely addressed what's happened in the past".

"We have to understand that these particular circumstances of human history have held these nations back and all they're trying to do is get on an equal footing," she said.

She added that financial payouts "are not the only way to make reparations", saying many countries impacted don't have the same access to financial credit in the way the UK does, or fair trade deals.

However on Friday a Downing Street spokesperson ruled out non-cash reparations, saying they "did not recognise" reports suggesting Sir Keir was open to this.

The prime minister's position was also criticised by Labour grandee Harriet Harman, who said he needs to have some cultural respect.

Reparations are usually defined as payments made by a country for damage or losses caused to other nations or their people.

There are various estimates for what the UK would owe, but last year a report co-authored by a United Nations judge concluded the UK owed more than £18tn to 14 countries.