The United States said Thursday it was providing another $152 million to prevent potential famine in Ethiopia's conflict-hit Tigray region as it urged unhindered access.

The US Agency for International Development said the funding brought the total US contribution for Tigray to $305 million and that the contributions, along with a US team on the ground, would support food, water, shelter and medical care to more than three million people.

The agency urged other donors to step up contributions "immediately," pointing to UN warnings that "there could be a risk of famine."

"The United States remains deeply concerned about the ongoing humanitarian crisis in Tigray and the lack of sufficient humanitarian funding to address it," it said in a statement.

"Large-scale assistance is urgently needed to prevent conditions in Tigray from worsening."

State Department spokesman Ned Price called for "full and unhindered access" to Tigray.

"It is absolutely critical for the humanitarian community to not only scale up its response but also to ensure that that humanitarian assistance is reaching the people in need," Price told reporters.

Ethiopia is a longstanding ally of the United States but Washington has been increasingly alarmed since Prime Minister Abiy Ahmed launched a military offensive in Tigray in November.

Secretary of State Antony Blinken has spoken of "ethnic cleansing" in Tigray, where Eritrean troops also intervened to fight the local ruling party.

Jake Sullivan, the national security advisor, pushed for expanded humanitarian access in a telephone call with Ethiopian Deputy Prime Minister Demeke Mekonnen.

Sullivan also pressed on the promised departure of the Eritrean troops and sought an investigation into atrocities, spokeswoman Emily Horne said.

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