BEDMINSTER, N.J., JAN. 17 -- When news came Wednesday night that war had broken out in the Persian Gulf, technicians at AT&T's national control center here watched as the volume of calls began to build, surging 25 percent above the normal rate for a weekday night.

Then, suddenly, the computer-generated graphs and numbers displayed on a wall-sized screen showed that the volume of calls had been cut in half. President Bush had begun his address to the nation, and Americans en masse had put down their phones to listen. Fifteen minutes later, brisk calling had resumed.

While American Telephone & Telegraph Co.'s long-distance network had no problem handling the press of domestic calls, international calls were another story.

Foreign traffic rose 40 percent between 7 p.m. and midnight Wednesday, with most of the increase involving the Middle East. Circuits became overloaded, prompting the frequent playing of recorded messages advising callers to try again later. At one point, the control center gave priority to calls coming in from, rather than going to, the crisis spot, a common procedure in times of emergency.

Calls to Israel skyrocketed again tonight following reports that Iraqi missiles had hit the country. AT&T reported that despite the crush, calls were going through, though often only after several tries.

Calls have not rise to and from one Mideast country: Iraq. AT&T lost direct-dial service at 7:03 p.m. Wednesday. Operator-assisted calls continued several hours longer but then they too stopped. Reports from Baghdad said the city's main telecommunications facility was hit in air strikes.

MCI Communications Corp. and US Sprint Communications Co. also reported circuits to the Middle East became overloaded Wednesday, as Americans tried to phone loved ones there and as military personnel called home. All three long-distance companies said domestic calling was normal today, while Middle East traffic was up, although not dramatically.

Calling by Washington area residents rose sharply around 7 p.m. Wednesday, then remained strong during the evening, according to Bell Atlantic Corp., owner of the Chesapeake & Potomac Telephone Cos.