(Adds WFP statement, details)

By Louis Charbonneau

UNITED NATIONS, May 6 (Reuters) - The United Nations estimates that "hundreds of thousands" of people in Myanmar are in need of help after a cyclone that killed nearly 22,500, a top U.N. humanitarian official said on Tuesday.

"Unfortunately we cannot tell you how many people are in need of assistance," Rashid Khalikov, director of the U.N. office for the coordination of humanitarian affairs, told reporters in New York. "We just clearly understand that it will probably be in the hundreds of thousands of people."

Khalikov also appealed to Myanmar to waive visa requirements for U.N. aid workers trying to get into the country days after the devastating cyclone, in the same way Pakistan and Iran did after disastrous earthquakes struck their countries.

Khalikov added that U.N. Secretary-General Ban Ki-moon had also asked the government to cooperate with the United Nations as much as possible to enable aid to reach people in the affected areas.

He said the U.N. aid officials gathered in Bangkok had only applied for their visas on Tuesday. They were unable to apply on Monday, he said, because the Myanmar embassy in Bangkok was closed due to a Thai holiday.

U.N. spokeswoman Marie Okabe said that Ban had written a letter to the junta's senior general, Than Shwe, though she declined to say whether he had mentioned the issue of visas for U.N. aid officials.

Khalikov was asked if he had a backup plan if the military government in Myanmar, formerly known as Burma, refused to issue visas to U.N. aid workers.

"The backup plan is to urge (the government) to issue visas," he said.

Separately, the World Food Program (WFP), the food aid branch of the United Nations, said in a statement that it began distributing food in cyclone-damaged areas in Yangon on Tuesday.

"WFP food assistance has now begun to reach persons who are without shelter or food resources in and around Yangon," said WFP country director Chris Kaye.

Kaye said the government had provided "some valuable cooperation". However, he indicated that the cooperation provided so far was insufficient.

"In order to meet the needs of the persons most badly affected by the disaster, much more cooperation will be required in the short term," Kaye said.

Khalikov said the United Nations was in the process of shipping additional emergency aid to Myanmar to supplement the more than 800 metric tons of food stocks the WFP has available in warehouses in Yangon.

However, Khalikov said he could not confirm that any of the U.N. aid coming from outside Myanmar had crossed the border.

The U.N. Central Emergency Relief Fund could also quickly release tens of millions of dollars in emergency aid, he said. (Reporting by Louis Charbonneau, editing by Philip Barbara)

AlertNet news is provided by