GENEVA, Dec. 6—War conditions are expected to force the suspension of United Nations food shipments to East Pakistani refugees in India until transportation problems are solved, reliable sources said today.

Shipments of blankets, which constitute a large part of the relief program, have already been suspended as a result of an order by the Indian Government closing the Calcutta airport to international flights.

The reliable sources said they were apprehensive about the prospects for delivering tens of thousands of tons of food, mainly rice, remaining to be transported to Calcutta by ship.

The Indian Government has closed the harbor of Calcutta at night and there is some doubt whether the 14 ships now headed for Calcutta with food will be able to unload.

In any event, it appears unlikely that Indian vehicles would have the surplus capacity to move the rice to the refugee area.

Further shipments of the rice, most of which is being bought from Thailand, are likely to be held up until it becomes clear whether the rice can be moved from Calcutta.

Officials of the United Nations aid program for East Pakistan itself, which is separate from the program in India, have already diverted relief shipments to Singapore.

The office of the United Nations High Commission for Refugees, headed by Prince Sadruddin Khan, which acts as the Focal point for the refugee program, had announced pledges of 382,000 tons of rice, about enough to feed eight million refugees for six months. About 170,000 tons had reached Calcutta before the outbreak of hostilities.

However, some donors, including the United States, had to make independent delivery arrangements. The United States had pledged 90,000 tons, and the Soviet Union 100,000 tons, and each had delivered about 27,000 tons, official sources said.