WASHINGTON - US authorities on Tuesday rushed search-and rescue teams to earthquake-hit Haiti as President Barack Obama offered his sympathy to the impoverished Caribbean nation.

The US Agency for International Development (USAID) said it was sending disaster response teams made up of 72 personnel, six search-and-rescue dogs and up to 48 tons of rescue equipment.

"This is a tragic situation and we will work alongside the Haitian government to provide immediate assistance in the rescue effort," said USAID administrator Rajiv Shah, who has been in office less than a week.

The White House said Obama was notified about the quake at 5:52 pm (2252 GMT), and asked staff to find out if embassy personnel were safe.

"My thoughts and prayers go out to those who have been affected by this earthquake. We are closely monitoring the situation and we stand ready to assist the people of Haiti," Obama said in a statement.

In Hawaii, US Secretary of State Hillary Clinton said government agencies were "still gathering information about this catastrophic earthquake."

"The United States is offering our full assistance to Haiti and to others in the region. We will be providing both civilian and military disaster relief and humanitarian assistance."

Former president Bill Clinton, now a UN special envoy for Haiti, said his "office and the rest of the UN system are monitoring the situation, and we are committed to do whatever we can to assist the people of Haiti in their relief, rebuilding and recovery efforts."