Defense Secretary Caspar W. Weinberger yesterday rejected a congressional proposal to put antiterrorist military units, including the Army's Delta Force, the Navy's Seals and other "special forces," under a single Pentagon command to make them more responsive to hijackings and other fast-breaking crises.

What the special forces need is not a new command structure but "more intensive training, better equipment" and a drive to encourage more people to join such units, Weinberger said at a breakfast meeting with reporters. "I don't think it's a panacea to put them all in together and just have one leader of the whole thing. We are quite capable, and do" put the special forces under a single command in an emergency.

"What we're doing is essentially the right thing," Weinberger continued. "I don't say it can't be improved. We need more training. We need to get more forward deployment" and special equipment. The Pentagon has plans to open an antiterrorist office in Europe to do the preparatory work for antiterrorist forces flying to trouble spots from the United States.

Rep. Dan Daniel (D-Va.), a senior member of the House Armed Services Committee, and Sen. William S. Cohen (R-Maine) have said the command of military special forces units, which in addition to the antiterrorist outfits include the Army Green Berets and other forces trained in unconventional warfare, is dangerously fractured and should be placed under a central authority. Daniel said he will hold hearings this year and sponsor legislation to require centralization of the special forces, designed to combat terrorism or slip behind enemy lines in a war.

"The big problem has been command and control," said Daniel, who advocates keeping special forces in their current locations but placing them under a single civilian director. Daniels cited foul-ups in the attempted rescue of Americans from the embassy in Tehran in 1980 and problems during the U.S. invasion of Grenada in 1983.

Cohen addressed the issue in an article for the January issue of Armed Forces Journal in which he said that the recent indictment of an Army special forces officer for fraud "indicates that congressional concern over the management supervision of special operations is not misplaced."