Iraq's continuing fortification of its defenses in Kuwait is prompting the United States to consider sending additional ground forces to Saudi Arabia to preserve what officials call a "credible" option for potential offensive action, according to senior U.S. officials and government analysts.

Maintaining such credibility is considered an important political goal by the Bush administration, Saudi Arabia and the exiled government of Kuwait, despite the absence of an international consensus supporting war against Iraq at this time.

Gen. Colin L. Powell, chairman of the Joint Chiefs of Staff, is expected to meet on Friday with Defense Secretary Richard B. Cheney to discuss Powell's recommendations on additional force deployments, which Powell has already discussed with Saudi officials and with U.S. tactical commanders in that country.

Cheney, asked yesterday if he had any sense that Iraqi President Saddam Hussein is seriously interested in a diplomatic solution to the nearly three-month-old gulf crisis, said he felt Saddam's recent moves are "designed principally to drive wedges between members of the coalition" backing U.N. economic sanctions against Iraq. Cheney told reporters after briefing legislators on Capitol Hill that "on the ground, he {Saddam} is continuing to build the size of his force."

Reports of the enhanced Iraqi fortifications, combined with the orchestrated settlement of Palestinians and Iraqis in captured Kuwaiti territory, have caused the administration to conclude that Saddam has not flinched in his determination to hold the country, the officials said. The defensive posture of Iraqi forces also has reduced the likelihood of an Iraqi attack on Saudi Arabia, they add, diminishing the fear that prompted the initial deployment of U.S. forces to the region.

The Iraqis "are continuing to dig in . . . to deploy . . . to fortify, and do all those things they need to do to hold onto Kuwait," a government analyst said on condition that he not be identified. "There is nothing we are aware of in terms of what's physically taking place {in Kuwait} that implies he's willing to divide the country or withdraw."

The sources said they are particularly concerned about what they describe as Iraq's construction of at least three defensive lines consisting of thousands of well-dug-in infantry troops backed by armor and protected by extensive mine fields, tank traps and barbed wire. These lines stretch hundreds of miles from the Persian Gulf westward into the desert along the border between Kuwait and Saudi Arabia.

Several officials said Iraq also beefed up its antiaircraft defenses after then-Air Force Chief of Staff Gen. Michael J. Dugan told reporters last month that any war with Iraq would start with massive U.S. air strikes in Kuwait and Iraq.

One official said there appears to be a "direct correlation" between Dugan's public comments and a major new deployment of Iraqi antiaircraft gun units in Kuwait.

Cheney fired Dugan on Sept. 17 for his public comments on U.S. attack plans. Pentagon officials said Iraq's relatively unsophisticated antiaircraft guns, capable of filling the sky with thousands of rounds of lead, will add to the risk of any U.S. air strikes.

Any decision on a U.S. assault remains at least weeks away, and has recently been complicated by several political and military factors, officials say. Critical spare parts and supplies for U.S. ground forces are still not in Saudi Arabia. Also, tactical officers lack a coordinated plan for commanding the multinational military forces in Saudi Arabia.

Cheney told legislators yesterday the United States is now working hard on the command problem, which has grown more vexing as Egypt, France, and Syria have begun dispatching thousands of troops.

The United States has more than 210,000 air, naval and ground military personnel in and around the Arabian peninsula, but only 150,000 ground troops in Saudi Arabia. The latter, supplemented by 100,000 European, Arab and Third World soldiers, would present an army of 250,000 against Saddam's 450,000 troops in Kuwait and southern Iraq.

Traditional doctrine dictates a 3-to-1 numerical advantage for any attacker, some U.S. military officials point out. "In my opinion, the present {U.S.} ground forces are nothing like big enough," said one defense official, who said he has advised senior Pentagon officials that "we need three or four more divisions" in Saudi Arabia if the United States and allies decide to force Iraqi troops out of Kuwait.

A senior official cautioned against assuming that such advice would automatically be accepted by President Bush, however. "I haven't met too many people in uniform who use the words, 'Enough already,' " he said.

Air Force officials have argued that U.S. and Saudi domination of the skies over the battlefield would be a crucial advantage, but Army and Marine commanders insist that no war was ever won from the air. There are more than 400 front-line U.S. combat aircraft in the gulf region.

The new Iraqi ground fortifications, officials said, are calculated to cause tens of thousands of American casualties if Washington approves a major ground offensive. The strengthened defenses also are intended to blunt the U.S. air power advantage by protecting Iraqi forces from bombs and rockets.

Pentagon officials say that if the president decides to prepare for offensive operations, "significant additional forces" in the United States and Europe must be notified to get ready for deployment. Sea transport of tanks, artillery and support equipment could take up to 60 days.

Units available for deployment include three "heavy" active-duty Army divisions in the United States: the 1st Infantry Division (Mechanized) at Fort Riley, Kan., the 4th Infantry Division (Mechanized) at Fort Carson, Col., and the 5th Infantry Division (Mechanized) at Fort Polk, La.

Army officials say U.S. troops in Europe may also be transferred to the Middle East, and House Armed Services Committee Chairman Les Aspin (D-Wis.) said yesterday that the Pentagon is considering redeploying the 82nd Airborne Division to Saudi Arabia after a possible brief home leave in the United States.

It is not clear when Iraq decided to begin strengthening its large field fortifications, but U.S. intelligence officials began to observe the movements in mid-September.

"It's time-consuming and it's a big investment," one administration official said.

"It's pretty clear to me that what they have in mind is to try and hurt us enough, if we attack, to make us quit," said a defense official who closely observes the Iraqi military.

The fortifications are not yet complete, officials said, but Iraqi engineering battalions have moved forward in large numbers to move earth, dig anti-tank ditches and pave new roads -- more than 500 miles worth -- for convoys of military supplies and rapid troop redeployment.

The first line of Iraqi defense starts about six miles from the Saudi border. The Iraqis have laid anti-personnel and anti-armor mines in the no-man's land between the defensive lines, as well as large drums of napalm that can be detonated by remote control. The lines include large earthen berms, or walls, to hide tanks and artillery in protected bunkers and shelters.

"Their purpose {in building these defense lines} is to draw our attacking military forces into a meat-grinder" by slowing their advance long enough to inflict withering artillery fire, an analyst said.

"Field fortifications are a real force-multiplier," a defense official said. "When you put a couple feet of sand and railroad iron over a tank, it's going to take an absolute direct hit to knock it out . . . and every day they get more solid and better-protected."

U.S. officials estimate that Iraq has 450,000 army and elite Republican Guard troops in the military zone that extends from Basra in southern Iraq into Kuwait and westward along the Iraqi-Saudi border.

The Iraqi occupation force is configured in three major concentrations, according to U.S. officials. About 100,000 troops are manning the main defensive lines along the Saudi border, while another 125,000 are dedicated to defending Kuwait and southern Iraq from amphibious assault from the Persian Gulf. The 150,000-member Republican Guard is south of Basra, ready for swift reinforcement of troops to the south or west. One official said this deployment of Saddam's most loyal and best-trained troops so far from Baghdad "tells us something about how the regime views its own stability."

Staff writer George Lardner Jr. contributed to this report.