Defense Secretary Caspar W. Weinberger said yesterday that the United States "has mine-sweeping capability in the Persian Gulf and it can be increased and will be increased."

Weinberger reacted strongly to suggestions that the Pentagon had not considered the possibility of mines in the gulf, where a Kuwaiti-owned oil supertanker flying the U.S. flag struck a mine on Friday while under U.S. Navy escort.

"You don't need a mine sweeper" to detonate and destroy mines, Weinberger said. "We have capabilities that are available when mines are discovered . . . . We did not look for {a mine} in that area {where the tanker Bridgeton was hit} because there have never been any mines in that area."

Appearing on ABC News' "This Week With David Brinkley," Weinberger declined to elaborate on the U.S. "mine-sweeping capability," saying, "What we don't do is talk about it."

Defense Department officials said there are several options for increasing the Navy's ability to deal with mines in the gulf:U.S. officials are negotiating with the Kuwaitis for the rights to base mine-sweeping helicopters there. Sources said they believe that the mine attack on the Bridgeton could give the United States more leverage in those negotiations. Pentagon officials said the Kuwaiti government so far has refused helicopter basing rights because "they don't want the high profile." The Pentagon could move an amphibious ship from the Indian Ocean to nearer the Persian Gulf, Defense Department officials said. The ship, part of a Marine amphibious group, could serve as the mother ship for mine-sweeping Sea Stallion helicopters. Several helicopters at a time could then be stationed on the USS LaSalle, a 521-foot command ship already in the gulf. The LaSalle is the only ship there large enough to serve as a base for the mine-sweeping helicopters. The United States also is continuing negotiations to base Sea Stallions on Saudi Arabian territory. The Saudis have refused so far.

One Pentagon official said no definite plan has been mapped out. "They're still talking and still working on it," he said.

Pentagon officials said yesterday that military leaders have virtually ruled out moving mine-sweeping ships to the Persian Gulf in the immediate future.

Of the 21 mine-sweeping ships in the U.S. Navy, only three are manned by active duty crews. The others are manned by reserve sailors who would have to be called to active duty. The active duty ships are based in Charleston, S.C., at least two weeks' steaming time from the Persian Gulf.

The Bridgeton and the Gas Prince were the first of 11 Kuwaiti oil vessels to be registered in the United States and escorted by a U.S. Navy convoy. The second convoy is expected to begin Aug. 6.

Rear Adm. Harold J. Bernsen, commander of the Middle East Task Force, said Saturday, "We're going to have to review the whole program . . . . We just don't have a great deal of {antimine} capability. We're going to do some mine-sweeping, I'm sure."

The United States has an 18-man team assisting the Saudis in mine sweeping in the Kuwaiti harbors.

Weinberger said in his television appearance, "We have swept the mines to the entrance to the Kuwaiti harbor very successfully -- detonated, I think, nine or 10 mines that were found there."

The Bridgeton was struck about 120 miles southeast of Kuwait and about 18 mines west of Farsi Island, which has been used by Iran as a base for speedboat attacks against gulf shipping. A Pentagon official said that until the Bridgeton struck the mine, no mines had been spotted that far outside the harbor area.

Pentagon officials are investigating whether the device was a tethered, or anchored, mine that could have been in place for months or years or a floating mine that might have been placed recently in front of the convoy.

After the explosion Friday morning, Capt. Daniel J. Murphy Jr., captain of one of the destroyers escorting the Bridgeton, said he thought the mine was brought from a nearby Iranian island in the predawn hours.

"We haven't gotten any proof

. . . The track record, however, would clearly point the finger to Iran," he said.

Some U.S. intelligence officials believe that Iranian officials based on Farsi Island overheard radio discussion from a U.S. warship that mentioned the exact route the U.S. naval convoy and reflagged ships were to take.

Iranian operatives then planted mines in their path, the U.S. officials believe.

Weinberger said yesterday that "it has not been firmly established that this was a mine."

However, most military officials are convinced it was.

In Kuwait yesterday, salvage sources said damage to the Bridgeton was more serious than originally estimated. Initial reports from the Bridgeton said only one compartment was flooded when the mine blew a hole 20 feet below the water line. But after examining the ship, the sources said the ship was flooded in four of its 32 compartments.

Sources in Kuwait said a patch might allow the Bridgeton to be partially loaded, but that any attempt to do so would be a political rather than technical decision.

Rep. Les Aspin (D-Wis.), chairman of the House Armed Services Committee, said, "We are very short of mine sweepers in the United States Navy. It's always considered a type of ship that is not a capital ship, not essential, not one of the more important ships. So we build fighting ships. We've always thought that what we would do would be rely on our allies for things like mine sweepers."

In response to a question, Aspin, who appeared with Weinberger, said that it was "possible but not likely" that U.S. involvement in the Persian Gulf could lead to war, shooting, loss of life and destruction.

"More likely, it's going to lead to a major attack on a facility like we had in Beirut, on the Marine guards. I think it's less likely to lead to Vietnam than it is likely to lead to a humiliating attack on a U.S. facility and then a crisis in this country about whether we should pull our forces back," Aspin said.