UN Secretary General Kofi Annan pleaded for fast assistance for the impoverished Caribbean state which has been hit by disastrous flooding for the second time in six months.

"The secretary general urges the international community to quickly provide Haiti, one of the world's poorest countries, the support it needs to recover from this devastating natural disaster," Annan's spokesman said in a statement.

The United States, France, Spain and Canada have all promised help, but the fastest response has come from Latin America.

Venezuela pledged one million dollars and sent a planeload of food, water and medicine on Wednesday, Information Minister Andres Izarra said.

Argentina sent a cargo plane with seven rescue workers and 10 tonnes of supplies.

A Brazilian plane carrying one tonne of medical supplies was also headed to Haiti on Wednesday.

Brazil leads the UN stabilization force in Haiti set up to restore order after Jean Bertrand Aristide resigned and fled at the end of February. Chile and other Latin American nations make up the bulk of the 3,300 force.

Brazilian President Luiz Inacio Lula da Silva sent Haitian President Boniface Alexandre a message of "solidarity".

Chile will send 20 tonnes in emergency aid expected to arrive in Haiti on Friday, a government spokesman. The cargo will include medicine and food and blankets and plastic covers.

Canada dispatched a military plane carrying 14 tonnes of supplies.

A first consignment of Spanish aid will leave Madrid on Thursday with 20 tonnes of aid, the Spanish foreign ministry said.

The International Committee of the Red Cross has appealed for 4.2 million Swiss francs (3.3 million dollars) to help victims of Tropical Storm Jeanne which battered Haiti over the weekend, unleashing fierce floods.

The French government has sent a first planeload of emergency supplies, while the US embassy pledged an initial 60,000 dollars in aid pending an assessment of the country's needs.

The United States and the Pan American Health Organization (PAHO) moved Tuesday to provide assistance to Haiti.

The US Agency of International Development (USAID) is providing 50,000 dollars to distribute relief supplies and has sent two experts to coordinate US relief efforts. PAHO has deployed an emergency team to Haiti.

More than 600 Cuban doctors and health experts, already established in Haiti, are assisting flood victims, Cuban officials said. Sixteen doctors are helping in the northwestern city of Gonaives, where more than 600 people died.