US President Barack Obama said Wednesday the United States will take swift, coordinated and aggressive measures to respond to the earthquake disaster in Haiti, and he has directed the administration to focus on saving lives.

Obama said the U.S. military has already mobilized its aerial relief team, overflying Haiti to assess the damage. He said civilian search and rescue teams will begin to arrive within a few hours.

The civilian rescue teams will be from Florida, Virginia and California. They will arrive throughout Wednesday and Thursday. Obama said more rescue and medical equipment and emergency personnel are being prepared.

"In disasters such as this the first hours and days are absolutely critical to saving lives and avoiding even greater tragedy," Obama said, directing the government to be as forward-leaning as possible in getting the help on the ground.

Obama has tasked Rajiv Shah, director of United States Agency for International Development (USAID) to be the administration's unified disaster coordinator. The USAID, the Departments of State and the Department of Defense are to bear the brunt of work in the relief effort.

"The people of Haiti will have the full support of the United States in the urgent effort to rescue those trapped beneath the rubble and to deliver the humanitarian relief -- the food, water and medicine -- that Haitians will need in the coming days," he said.

Apart from sending relief to Haiti, Obama said the administration is working to account for US Embassy personnel and their families in Port-au-Prince, capital of Haiti, as well as US citizens who live and work in Haiti. CNN said there are over 40,000 US citizens in Haiti.

Obama said the United States will be working closely with partners including NGOs, the United Nations Stabilization Mission in Haiti, and other partners in the region and around the world.

"This must truly be an international effort," he said.

Shah, the head of USAID, told MSNBC Wednesday relevant US agencies worked throughout the night to make sure effective search-and-rescue operations and other support reach Haiti as quickly as possible.

Haiti was struck by a magnitude 7 earthquake on Tuesday. The quake caused extensive damage, possibly killing hundreds.

(Xinhua News Agency January 14, 2010)