RANGOON, Burma — A new cyclone was developing off the Burmese coast yesterday, threatening up to 2 million survivors of cyclone Nargis who have been living for 12 days without adequate food, shelter, or drinking water.

“The potential for the development of a significant tropical cyclone within the next 24 hours is upgraded to good with the only limitation being temporary land interaction,” a report by the Joint Typhoon Warning Centre, an American government agency, said.

Yet, once again, no warnings were broadcast on Burmese state press.

Residents of Rangoon, which some forecasts said would receive another direct hit, were aware of “bad weather” to come from foreign broadcasts, the Internet, and word of mouth. In the Irrawaddy delta, where hundreds of thousands of ailing Nargis survivors are living in squalor, few have access to radio. The storm, if it arrives, will come without warning.

Amanda Pitt, a United Nations spokeswoman, said the “already weak” survivors would struggle to withstand a second battering. The new storm would hamper “people’s ability to survive and cope with what happened to them … This is terrible,” she said.

The new storm is not expected to be as strong as the last one — whose 120mph winds whipped up a 12-foot wall of water — but it is believed to carry an average month’s worth of rain fall. Heavy rains will further damage already broken roads and bring misery to unprotected survivors.

International agencies believe that at least 100,000 people were killed by Nargis, although the Burmese regime stands by a lower figure. Relief supplies from the United Nations and charities have so far reached only 270,000 survivors — a fraction of the total number.