WASHINGTON, Oct. 23 (Xinhua) -- U.S. President Barack Obama has assured German Chancellor Angela Merkel in a phone call that the United States "is not monitoring and will not monitor" her communications, said the White House on Wednesday.

According to a White House statement, Obama and Merkel spoke by phone regarding the latest allegations that the U.S. National Security Agency (NSA) intercepted the communications of the German Chancellor.

"The United States greatly values our close cooperation with Germany on a broad range of shared security challenges," said the White House, adding that the U.S. is reviewing its intelligence- gathering to ensure a balance of security and privacy.

The two leaders also agreed to intensify further cooperation between the two countries' intelligence services, said the White House.

The German government said in a statement on Wednesday that it has received information that U.S. intelligence is spying on the mobile phone communications of Merkel.

In a White House daily briefing on Wednesday, White House spokesman Jay Carney sidestepped a question about whether Merkel's phone calls may have been monitored by the NSA's surveillance program.

According to the German statement, Merkel called Obama and said that she views such practices, if confirmed, as "completely unacceptable."

Merkel is the latest U.S. ally to express worry about the NSA's intelligence surveillance programs, following French President Francois Hollande's complaining about NSA's spying on millions of French citizens earlier this week.