The Pentagon has selected three commercial air charter companies to help rush more than 1,400 troops to Kuwait to participate in joint war games.

The exercises, due to last until mid-September, are part of a longstanding semiannual series of cooperative Kuwaiti-American war games, code named ''Intrinsic Action." The latest exercises were supposed to begin in October and November but, following the defection of two senior Iraqi officials to Jordan earlier this month, the Pentagon accelerated the schedule.Most of the U.S. troops participating in the exercises are soldiers from the 1st Armored Cavalry Division, based at Fort Hood, Texas, and Marines from Camp Pendleton in California.

Lt. Linda Pepin, an Air Force spokeswoman for the U.S. Air Mobility Command at Scott Air Force Base, Ill., said the command chartered Boeing 747 aircraft

from Tower Air and World Airways, and Lockheed L-1011 aircraft from American TransAir, for six of the 27 flights that will be needed to move the troops into the theater. As of Wednesday, all six commercial charters were en route to the Persian Gulf, she said.

U.S. Air Force and Army advance teams began arriving in Kuwait City on Tuesday. Included in the flights were 66 members of the 621st Tanker Airlift Control Element from McGuire Air Force Base, N.J., 93 soldiers from the 1st Armored Cavalry Division, and almost 150,000 pounds of cargo and support equipment.

Secretary of Defense William Perry said last week that the United States would increase its military presence in the gulf as a precaution, following what he said were intelligence reports of unusual troop movements in Iraq. Mr. Perry said that one of the defectors, Lt. Gen. Hussein Kamel Hassan Majeed, indicated that Iraqi President Sadaam Hussein may be considering a second invasion of Kuwait.

In addition to accelerating Intrinsic Action, the Pentagon is moving military cargo ships carrying enough supplies to support more than 22,000 troops to the gulf.

Iraq has denied moving troops and said it has no intention of going to war with either Kuwait or Jordan, which has granted asylum to the defectors and their families.

Jordan is the only Persian Gulf state that sided with Iraq during the gulf war. With U.N. economic sanctions against Iraq in place, Jordan is Iraq's only conduit to the outside world. Iraq, in turn, supplies virtually all of Jordan's oil.

In response to criticism that the recent U.S. buildup is an overreaction, U.S. military officials say Iraq's history of unexpected aggression gives them reason to be cautious.

In a tense two weeks last October, the United States rushed thousands of troops and tons of military materiel to the gulf after satellite

reconnaissance revealed a significant movement of Iraqi troops toward Kuwait. In response, the Iraqis stood down, and the United States claimed its rapid military buildup had nipped another war in the bud.

The United States has no troops permanently stationed in Kuwait. But the Pentagon maintains an arsenal of heavy armor there for use by troops that would be flown to the gulf state in the event of an emergency.

The pre-positioned stocks are one of the legacies of the gulf war. The Pentagon's problems transporting supplies and troops quickly to the region in 1991 taught U.S. defense officials the value of keeping equipment as close to possible theaters of conflict as possible.