A rebel leader in eastern Democratic Republic of Congo says his fighters will withdraw from a key city at the request of the US.

Corneille Nangaa's statement came days after US Secretary of State Marco Rubio said the capture of Uvira by rebel forces violated a peace deal, and the US would "take action to ensure promises made to the President [Donald Trump] are kept".

Nangaa said that rebel forces would pull out of the city as a "trust-building measure".

The US accuses Rwanda of backing the rebels. Rwanda denies the allegation, but its President, Paul Kagame, signed a peace accord on 4 December with his DR Congo counterpart, Felix Tshisekedi, at a ceremony in Washington hosted by Trump.

The US president hailed the deal as "historic" and "a great day for Africa".

The rebels were not signatories to it - and have been taking part in a parallel peace process led by Qatar, a US ally that has strong ties with Rwanda.

Nangaa is the coordinator of the Alliance Fleuve Congo (AFC), a coalition of rebel groups. It includes the M23, the most powerful force that European countries, along with the US, say is backed by Rwanda.

DR Congo's army is supported by troops from neighbouring Burundi.

The M23's capture of Uvira was a major blow to them, as the city is only 27km (17 miles) from Burundi's economic capital, Bujumbura, on the northern tip of Lake Tanganyika.

"AFC/M23 will unilaterally withdraw its forces from the city of Uvira as requested by the United States mediation," Nangaa said in a statement, adding that this was being done to give the Qatar-brokered peace process the "maximum chance to succeed".

He did not indicate when the withdrawal would take place, but called for the deployment of a "neutral force" to monitor a ceasefire and to prevent DR Congo's army from regaining control of territory it had lost.

About 200,000 people have fled their homes in eastern DR Congo since the latest round of fighting started early this month, the UN says.

At least 74 people, mostly civilians, had been killed, and 83 others had been admitted to hospital with wounds, it added.

Eastern DR Congo has been wracked by conflict for more than 30 years, with numerous peace initiatives aimed at ending the fighting having failed.

The Trump administration hopes that its peace initiative will work and pave the way for US companies to boost their investments in the resource-rich region.

The US State Department said in 2023 that DR Congo had an estimated $25tn (£21.2tn) in mineral reserves.

This included cobalt, copper, lithium, manganese and tantalum - needed to make the electronic components used in computers, electric vehicles, mobile phones, wind turbines and military hardware.

The rebels began a major advance earlier this year when they captured Goma, the capital of North Kivu province, on the border with Rwanda.

At the time, South African troops were deployed to help DR Congo's army, but they were forced to withdraw after the M23 seized the city in January.

Shortly afterwards the rebels captured the next big city in eastern DR Congo, Bukavu, capital of South Kivu province.

The move on Uvira - the government's last major foothold in South Kivu - came after the rebels broke the defence lines of the DR Congo army, militias allied with it and Burundian troops.

The offensive started a few days before Kagame and Tshisekedi flew to Washington to ratify the agreement first hammered out in June.