The Red Cross estimates 45,000-50,000 people have died in Haiti's devastating¹ earthquake, as rescue teams race against time to find survivors².

国际红十字会估计此次海地地震造成大约45000到50000人死亡，救援队伍正在争分夺秒抢救幸存者。

The US is sending up to 3,500 troops and 2,200 marines but correspondents say aid is so far only trickling⁴ in.

President Barack Obama pledged one of the biggest relief efforts in recent US history and said Haiti would "not be forgotten" in its hour of need.

Aid groups say they need food, water, medical supplies and lifting equipment.

President Obama and French President Nicolas Sarkozy, working with Brazil, Canada and other countries, will organise⁵ a conference on reconstruction⁶ in Haiti, the French presidency⁷ has announced.

The Red Cross estimates that up to three million people in Haiti have been affected⁸ by Tuesday's earthquake.

Many are spending another night without shelter or in makeshift临时的 camps in the ruined capital, Port-au-Prince.

Correspondents there say bodies are piling up in the streets and there is still no sign of a co-ordinated relief effort.

Speaking in Washington on Thursday, Mr Obama said some US rescuers were already on the ground在地上，当场 in Haiti and more were on their way.

He promised the country "every element of our national capacity, our diplomacy⁹, and development assistance, the power of our military and most importantly, the compassion¹⁰ of our country" following the disaster.

"To the people of Haiti, we say clearly and with conviction信念，定罪, you will not be forsaken抛弃，遗弃, you will not be forgotten," he said.

However he warned it would take time for much-needed help to reach people.

Mr Obama also promised an immediate¹² $100m for Haiti's relief effort救灾工作 and said that investment would grow over the coming year to aid long-term recovery.

The first 100-strong contingent¹³分遣队 from the US Army's 82nd Airborne Division was expected to arrive in Haiti by the end of Thursday, with several hundred more due by Friday.

The USS Carl Vinson aircraft carrier and the USS Bataan, carrying a marine³ expeditionary远征的，考察的 unit, are on their way.

Gen Douglas Fraser, head of the US Southern Command, told reporters that logistics后勤 would be the key to providing relief and that US forces would strive to make Port-au-Prince's port functional¹⁴ again.

The US Federal Aviation Authority earlier temporarily stopped civilian¹⁵ relief flights to Haiti at the Haitian government's request because there was not enough space on the ground for more planes.