Turkey closed its main border crossing into Iraq for three hours Friday, slowing the flow of allied supplies to Kurdish refugees in the region, U.S. military officials said.

The action followed Turkish newspaper reports alleging that U.S. troops were smuggling weapons to Iraqi Kurdish guerrillas in northern Iraq. U.S. and Turkish officials denied reports of arms smuggling.On Thursday, the allies plunged 50 miles deeper into northern Iraq, taking control of a zone that includes a bombed airfield and four of Saddam Hussein's opulent villas. (See story on A7.) Iraq apparently had planned to blow up one of the villas rather than allow it to fall into allied hands but canceled the plan Thursday night, Iraqi officials said. It was not known what the villa contained.

The border was closed at about 7 a.m. and opened three hours later, said Col. Don Kirchoffner, an American spokesman for the allied military effort based at Incirlik air base.

Reporters at the border said that only military vehicles were allowed across the frontier when it was reopened at 10 a.m. and that civilian aid trucks weren't allowed through until about 11:30 a.m.

Turkish officials said the border was not technically shut, but that they had decided to enforce rules requiring special legal documents for foreign military vehicles carrying relief supplies.

Reports of allied arms-smuggling to the Kurds caused an outcry in Turkey, where there have been increasing charges that the country's sovereignty is being violated by the foreign troops relocating hundreds of thousands of Iraqi Kurdish refugees.The border closure occurred at the Habur River Bridge, six miles

northwest of Zakho, the center of the allied relief effort in northern Iraq.

Three vehicles of a U.S.-Canadian military medical team, seven U.S. Marine trucks and 22 civilian trucks were temporarily halted at the crossing.

Most of the supplies for the Kurdish refugees have been trucked overland, although a portion has been flown in by helicopter. The Turkish government took no action Friday to halt relief flights.

In another development, Turkey decided Friday to expel a British reporter who alleged that Turkish troops were stealing supplies intended for refugees.

Regarding the reporter, a senior allied military official said: "There has been some indication that the Turkish government is unhappy with an article by a member of a press," the official said.

Turkish authorities ordered the reporter, Robert Fisk, expelled on Friday. He was detained after reporting in the London newspaper, the Independent, that Turkish soldiers had been stealing food from some camps east of Silopi.

The government charged him with "insulting the Turkish army."

The military, which has seized power three times in Turkey in the last three decades, is considered by many the guardian of Turkish nationalism. Harsh criticism of it is considered taboo.

The border closing came as U.S., British, French and Dutch forces were expanding relief efforts for the Kurds, displaced after Saddam Hussein's soldiers crushed their rebellion following the Persian Gulf war.

During the advance in northern Iraq, the allied force set up guard posts and checkpoints and took control of a battered air strip near Sirsenk, which is expected to become a landing place for relief supplies.

They apparently planned to blow up one of Saddam's hilltop summer palaces to prevent the allies using it as a headquarters or observation post. But Thursday night the officials canceled the event amid reports that U.S. and British forces had told the Iraqis they did not plan to occupy the palace.

Military leaders said widening the security zone was necessary to lure more Kurdish refugees down from mountain camps.