The United States is in talks to invest billions of dollars in mineral-rich Congo and wants to help end a conflict raging in the country's east, President Donald Trump's senior adviser for Africa said during a visit on Thursday. 

Democratic Republic of Congo, which has vast reserves of cobalt, lithium and uranium among other minerals, has been fighting Rwanda-backed M23 rebels who have seized swathes of its territory this year.

The US, which on Wednesday sent shockwaves across the world by announcing a 10% baseline tariff on all imports, said last month that it is open to exploring critical minerals partnerships with Congo after a Congolese senator contacted US officials to pitch a minerals-for-security deal.

"You have heard about a minerals agreement. We have reviewed the Congo's proposal, and ... the president and I have agreed on a path forward for its development," US senior adviser Massad Boulos said after meeting Congo President Felix Tshisekedi in Kinshasa. 

The details of any potential deal, or Congo's proposal, were not made public on Thursday.

Congo's minerals, which are used in mobile phones and electric cars, are currently dominated by China and its mining companies.

How the US will operate in Congo is unclear, but Boulos suggested that US companies will be involved. 

"Rest assured, American companies are operating transparently and will stimulate local economies. These are multibillion-dollar investments," he said. 

Joseph Bangakya, Congolese parliamentarian and president of a Congo-US friendship parliamentary group, told Reuters that MPs were preparing a bill to promote the Central African country's business climate.

"It is essential for our country to achieve a trade agreement with the United States," he said.

Boulos added that the US wants to help forge peace in the east where thousands have been killed and hundreds of thousands forced to flee amid M23's advance, which has seen the group take over eastern Congo's two largest cities. 

"We want a lasting peace that affirms the territorial integrity and sovereignty of the DRC," he said. "There can be no economic prosperity without security."