April 9 (Reuters) - The United States is attempting to

broker a deal that would ensure re-opening of a major tin mine

in war-hit eastern Congo, four sources briefed on the

negotiations told Reuters.

The fate of Alphamin's Bisie mine was a point of discussion

during the recent visit to Kinshasa by U.S. President Donald

Trump's senior Africa adviser, Massad Boulos, the sources said,

though Washington's involvement goes back several weeks.

Washington and Kinshasa are also in talks about a broader

deal on critical minerals partnerships, after Congo pitched a

minerals-for-security deal to the Trump administration.

The Bisie mine produced 17,300 tons of tin last year,

representing around 6% of global mine supply.

Alphamin announced last month it would temporarily cease

operations at Bisie as Rwanda-backed M23 rebels advanced nearby,

taking the strategic town of Walikale and openly threatening the

mine.

M23 withdrew from Walikale last week, describing the move as

a goodwill gesture ahead of planned Qatar-brokered peace talks

with the government.

However, the sources told Reuters M23 made the decision

because Washington got involved directly with Congo and Rwanda.

They said Washington pressed for M23 to withdraw 150

kilometres from the mine and for Congo's army not to attack the

rebels.

The United Nations and Western governments say Rwanda has

provided arms and troops to the ethnic Tutsi-led M23.

Rwanda has denied backing M23 and says its military has

acted in self-defence against Congo's army and a militia founded

by perpetrators of the 1994 genocide.

Boulos was expected to raise the issue with Rwandan

President Paul Kagame during his stop in Kigali on Tuesday, the

sources said.

Boulos told reporters in Kigali that Washington hopes

Alphamin will "make some announcements soon with regards to

resuming their operations". The company did not respond to a

request for comment.

"We definitely encourage them to resume their operations,

and we appreciate the dialogue that is ongoing," Boulos said.

(Additional reporting by Philbert Girinema in Kigali

Writing by Robbie Corey-Boulet

Editing by Ros Russell)