UNITED NATIONS - U.N. chief Ban Ki-moon asked the Security Council on Monday to approve 3,500 more peacekeepers for Haiti -- a nearly 40 percent increase -- to help cope with the chaos that followed last week's earthquake.

Diplomats said they expected a vote in the 15-nation council on Tuesday to authorize the temporary boost for the U.N. mission, known as MINUSTAH, and anticipated that Ban's request would be met in full.

The members of the council expressed their support to the proposal of the secretary-general to increase the overall level of MINUSTAH to support the immediate recovery and stability efforts, Chinese Ambassador Zhang Yesui, this month's council president, told reporters.

The members of the council are working very hard on the rapid response to the proposal.

Ban, speaking to reporters after addressing a closed-door council session on a six-hour trip he made to Haiti on Sunday, said the reinforcement of the peacekeepers with 2,000 more troops and 1,500 more police would be for six months.

Media reports have said the U.N. blue-helmets are struggling to keep order and deliver aid after the January 12 quake wrecked the Haitian capital Port-au-Prince and killed as many as 200,000 people.

The heartbreaking scenes I saw yesterday compel us to act swiftly and generously today and over the longer term, Ban said. He had earlier told the council that difficulties in delivering aid could cause security to deteriorate.

BRAZIL, EU MAY CONTRIBUTE

Diplomats said a group of Security Council members was drafting a resolution to approve the proposed increase in MINUSTAH. They said the delay in the vote until Tuesday was to allow governments of council members to review it overnight.

The number of peacekeepers in Haiti currently stands at just over 9,000. Ban's proposal would take the figure to more than 12,500 -- a total of 8,940 troops and 3,711 police.

Ban's 3,500 figure was considerably more than the 1,250 extra peacekeepers U.N. officials had been speaking about on Sunday, suggesting that the challenge was now considered greater than ever.

France's U.N. ambassador Gerard Araud said the European Union was considering contributing some police and Brazilian Foreign Minister Celso Amorim said Brazil, which commands MINUSTAH, was ready to increase its troop level. It was unclear how quickly the additional forces might be deployed.

Among buildings destroyed in the quake was the U.N. headquarters in Port-au-Prince.

Spokesman Martin Nesirky said the confirmed U.N. death toll from the quake currently stood at 46 and that more than 500 U.N. employees were unaccounted for.

U.N. officials say all but about 40 of those unaccounted for are local staff, many of whom may have survived but have not been contacted. Ban has called the quake the single worst calamity ever to strike the United Nations.

(Editing by Claudia Parsons)

China U.S. Ban United nations