President Bush offered condolences and Secretary of State Condoleezza Rice (search) said the U.S. was ready to help Pakistan and India after an earthquake on Saturday killed thousands near their northern border.

No Americans were immediately known to be among the injured or killed reported by officials following the 7.6-magnitude earthquake, the State Department (search) said. The quake also rattled portions of neighboring Afghanistan.

More than 18,000 U.S. forces are in Afghanistan, but no casualties or structural damage was reported by U.S. Central Command (search), spokesman Major. Richard McNorton said. No U.S. troops were conducting operations on the ground in Pakistan, he said.

Bush was briefed by aides at the White House on the quake.

"The thoughts and prayers of the president and the first lady are with the families, friends and loved ones of the victims," spokesman Ken Lisaius said.

Rice said she spoke with the foreign ministers of Pakistan and India to convey sympathy and offer whatever assistance may be needed. She called the earthquake "a terrible tragedy for the people of the region."

"At this difficult time, the United States stands with its friends in Pakistan and India, just as they stood with us and offered assistance after Hurricane Katrina (search)," Rice said in a statement.