A group of sunny but barren Caribbean islands with about as many people as Seat Pleasant, Md., is planning to ask the United States for a full-fledged foreign aid program - despite the fact that it is a British colony.

"The American government should make a good port for us," said James McCartney, chief minister of the Turks and Caicos islands. "We need decent roads, an up-to-date airport, power and water."

McCartney, 32, is a dapper night club owner who was elected chief minister of the island group a year ago. Although the islands are a British colony, McCartney says the British contribution to their economy is inadequate.

He will have a chance to make his request for the U.S. aid next week when British and American diplomats sit down to renegotiate an agreement giving the United States land on two of the islands for an Air Force tracking station and a Coast Guard facility.

For the first time, representatives of the 7,000 inhabitants of Turks and Caicos will be sitting in on the talks - a delegation of three headed by McCartney.

British and American diplomats who will participate in the talks find it difficult to take McCartney's demandds seriously.

"It's such small beer, really," one said. "You needn't necessarily talk about money, but small things that can subsumed into the bases budget. Maybe the Seabees could resurface the road."

But McCartney has big plans for his little islands, and resurfacing the road is not enough.

The United States, he said in an interview, "goes around the world throwing money to people who are your enemies. We really deserve help because we offer something to the Unites States."

There is a U.S. facility on each end of the seven-mile-long island Grand Turk, he said. Both are parts of an Air Force tracking station, with one U.S. officer and no enlisted men stationed there, a U.S. official said.

On nearby South Caicos there is a small Coast Guard station.

The U.S. facilities in the British-financed civil service are virtually the only employers on the islands. The residents who do not have jobs are fishermen, McCartney said.

There are no natural resources, no agriculture and no industry. "Everything is imported," he said.

The islands were once linked to Jamaica and the short-lived Federation of the West Indies, but returned to the British fold when Jamaica became independent in 1962.

The chief minister, who built up his Peoples Democratic Movement while running his Junkanoo bar and social club, says he hopes to start a free port and develop some tourism and light industry.

"But first we need infrastructure," he said. "If we ask an investor to build a hotel, he says, "I'll build a hotel, but first you put up a power line and build an airport."

The only airport on the islands that can handle large planes is on the U.S. Air Force base. The Air Force maintains it and permits commercial flights to land there.

The demand is so light, however, that the only airline to serve the island stopped flying for three months recently. Since there is no passenger service by boat in or out of the islands, even the chief minister was stranded.

Fortunately, Grand Turk is a good stop for private planes that are being ferried between North and South America," McCartney said. "We would go out to the airport and try to hitch a ride. We call it 'air hiking.'"