UN Security Council concerned over imminent attack in Sudan's North Darfur

UNITED NATIONS (Reuters) - The U.N. Security Council on Saturday expressed its "deep concern" over an imminent attack on al-Fashir in Sudan's North Darfur region by the Rapid Support Forces (RSF).

War erupted in Sudan one year ago between the Sudanese army and the paramilitary RSF, creating the world's largest displacement crisis.

Al-Fashir is the last major city in the vast, western Darfur region not under control of the RSF. The RSF and its allies swept through four other Darfur state capitals last year, and were blamed for a campaign of ethnically driven killings against non-Arab groups and other abuses in West Darfur.

The Security Council, in a statement, "expressed their deep concern over an imminent offensive by the Rapid Support Forces and their allied militias" against the city of al-Fashir.

"They called on the Sudanese Armed Forces and Rapid Support Forces to end the build-up of military forces and to take steps to de-escalate the situation," the statement said.

Top U.N. officials warned the Security Council last week that some 800,000 people in al-Fashir were in "extreme and immediate danger" as worsening violence advances and threatens to "unleash bloody intercommunal strife throughout Darfur."

(Reporting by Michelle Nichols; Writing by Eric Beech; Editing by Daniel Wallis and Chris Reese)