CRISIS IN THE PERSIAN GULF : Iraqi Military Hampered by Critical Shortages : Embargo: U.S. officials say that a lack of materiel has reduced the mobility and training of troops. More shortages are likely.

The Iraqi military is suffering from critical shortages of tires and lubricants, limiting the mobility of ground troops and forcing the Iraqi air force to curtail training flights, according to new U.S. intelligence reports.

U.S. officials expect that the trade embargo against Iraq, imposed by the United Nations after the invasion of Kuwait in August, will produce more shortages of key military materiel, including spare parts for vehicles and aircraft.

The economic sanctions are sapping the strength and morale of Saddam Hussein’s army even as the more than 300,000-strong Arab and Western force arrayed against him grows larger and begins to resolve serious problems with its command structure.

Short supplies of a gasoline additive, which helped force Baghdad to announce gas rationing late last week, eventually will affect the Iraqi military as well, according to U.S. analysts. Gasoline shortages would limit Iraq’s ability to train for and sustain prolonged combat operations, officials said.

Time has decisively turned against the Iraqi president, senior American government leaders indicated.

In addition, the United States emphasized this weekend that it believes it has all the authority it needs from the United Nations to justify an attack on Iraq and Iraqi forces in Kuwait, should it decide to do so.

Defense Secretary Dick Cheney said in Paris: “Given the request by the government of Kuwait under Article 51 of the U.N. Charter--the inherent right of self-defense--we do not require any additional authority.”

The Bush Administration also believes that it does not need further provocation from Iraq to justify the use of force to liberate Kuwait. U.S. officials cite the Aug. 2 invasion of Kuwait, the seizure of thousands of foreign hostages, violations of foreign embassies and a campaign of terror against Kuwaiti citizens as sufficient cause for war against Iraq.

And although Cheney and other Bush Administration officials continue to stress a preference for a peaceful solution to the gulf crisis, they are clearly nearing the point where they are ready to contemplate offensive action to enforce the demand that Hussein surrender Kuwait.

An early resort to force would cause serious political ruptures with moderate Arab states and some European allies, who would prefer a negotiated solution. But the only major military problem to be resolved on the ground is poor coordination among the multinational military units now deployed in Saudi Arabia, according to military experts.

Gen. Colin L. Powell, chairman of the Joint Chiefs of Staff, left Washington for Saudi Arabia on Sunday to consult with U.S. and allied commanders as well as Saudi government officials. Powell hopes to iron out these command-and-control problems, which remain a source of deep concern to U.S. leaders.

The Pentagon’s chief policy adviser, Undersecretary Paul D. Wolfowitz, also will travel to Saudi Arabia this week to discuss command concerns. Cheney also plans a trip to the desert kingdom shortly to work on the problems, aides indicated.

Troops from about two dozen countries are now encamped in the desert to defend Saudi Arabia. Although the United States is satisfied with its command arrangements with Saudi Arabia and Britain, there are continuing tensions with French forces, who insist on an independent command structure.

In addition, command links with many of the other members of the coalition are virtually non-existent. Because the 200,000-member U.S. force in the region will carry out the bulk of military operations in the event of war, U.S. commanders want clear authority to direct allied forces to support the major U.S. effort.