The Reagan administration, fighting a lawsuit brought by 110 members of Congress, told a federal judge yesterday there is no reason to invoke the War Powers Resolution despite a series of U.S.-Iranian military incidents in the Persian Gulf.

But Alan Morrison, representing the congressional group that wants the law invoked, contended that "if this set of circumstances doesn't cause the triggering of the war powers act, I don't know what would, short of all-out war."

The arguments came at a brief hearing before U.S. District Court Judge George Revercomb on a three-month-old suit that seeks a court order requiring President Reagan to comply with the 1973 law.

Revercomb took the case under advisement and said he would rule later.

The law was enacted by Congress in the waning days of the Vietnam war.

It requires a report from the White House within 48 hours after U.S. forces are sent into areas of imminent hostilities. Within 60 days after that, under some circumstances, the troops would have to be withdrawn unless Congress approves their deployment.

Reagan has refused to invoke the law for his Persian Gulf policy, which involves putting U.S. flags aboard 11 Kuwaiti tankers and protecting them with Navy convoys in the war-torn gulf.

Although Reagan and his administration have said the law is unconstitutional, that issue was not discussed in yesterday's hearings. Robert Cynkar, a Justice Department attorney who represented the administration, explained that "constitutionality isn't the issue here."

The suit seeks only to require the White House to submit the report that is required by the 48-hour provision.