Saudi Arabia's King Abdullah told U.S. President Barack Obama that his country would prop up Egypt's President Hosni Mubarak if the United States withdrew its aid program, The Times said on Thursday.

Abdullah told Obama not to humiliate Mubarak, who is under pressure from protesters to quit immediately, in a telephone call on January 29, the newspaper said, citing a senior source in Riyadh.

Open gallery view U.S. President Barack Obama shaking hands with Saudi King Abdullah at a bilateral meeting in Riyadh, Saudi Arabia on June 3, 2009. Credit: AP

Obama's administration has wavered between support for Egypt in Washington's conflict with militant Islam and backing for Egyptians who have been protesting for weeks to demand Mubarak and his government quit.

The United States has long nurtured its alliance with key ally Egypt, giving billions of dollars in aid as it seeks to influence affairs in a region whose autocratic rulers are struggling to contain social discontent.

The United States has stopped short of endorsing calls for Mubarak, 82, to leave office immediately. He said last week he would step down in September when an election is due.

On January 28, the White House said the United States would review $1.5 billion in aid to Egypt. Officials later said no such review was planned currently.