UN Secretary-General Ban Ki- moon said Wednesday that the relief operations remain complex, but "we are now seeing significant progress" in relief operations in the quake-devastated Haiti.

"The aid operation is complex. But we are now seeing significant progress," Ban told reporters after he briefed the UN Security Council on his recent trip to Britain, Ethiopia and Cyprus, which took him to the international conference on Afghanistan, the Summit of the African Union and the talks with leaders of the divided Cyprus.

"The situation is largely calm," he said. "Food distribution is growing smoother by the day, and we have now reached about one million people. Banks, markets and schools are beginning to re- open."

On Wednesday morning Ban had a meeting with the UN special envoy to Haiti, former U.S. President Bill Clinton, who has agreed to take on an expanded leadership role in coordinating international aid effort.

"In particular, he will provide strategic guidance in our work for Haiti's early recovery and long-term reconstruction, with a special emphasis on mobilizing international support and donor funding," he said.

"We agreed that one of the most urgent needs right now is shelter," he said. "The storm season is just months away. Important as they are, tents alone will not suffice."

"In meeting this and other needs, we agreed that we must move as urgently as possible to develop a clear strategy that mobilizes all UN agencies and their partners, including national governments, NGOs (non-governmental organizations) and the private sector," he said.

"The secretary-general said he could not think of a better suited leader than President Clinton to do this," UN spokesman Martin Nesirky told a news briefing. "The aim is to provide strategic guidance to the UN involvement at the international level."

UN Children's Fund (UNICEF) Executive Director Ann M. Veneman was leaving Wednesday for the Dominican Republic on the first stop of a visit to Haiti, as the agency launches a massive immunization campaign aimed at reaching 500,000 children under the age of seven. She is scheduled to arrive in Port-au-Prince, the capital of Haiti and a city devastated by the quake, on Thursday and spend the day with children in the city and visit an immunization centre for measles, diphtheria and tetanus, all of which can be deadly in times of crises.

Haiti was devastated by the Jan. 12 earthquake, which killed up to 300,000 people and brought unimaginable suffering to the Caribbean nation already experiencing decades of conflict and poverty.