CAIRO, JULY 19 -- Iraqi President Saddam Hussein, pressing his campaign to become the preeminent leader in the Arab world, won approval today from Iraq's compliant parliament for a revised constitution that would make him president for life in a legislative vote later this year.

The new demonstration of the Iraqi leader's unchallenged authority in Baghdad came on the heels of a series of ominous public threats by Saddam Hussein against Kuwait and other Persian Gulf states that sent the worried Kuwaitis in search of diplomatic support and drew a strong reaction from U.S. officials.

The crisis flared earlier this week when Iraq accused Kuwait -- its former ally in the eight-year Persian Gulf War with Iran -- of stealing Iraqi oil, encroaching on its territory and conniving with the United States to depress oil prices, an outburst seen by many gulf analysts as the latest use by Saddam Hussein of bellicose rhetoric in his effort to dominate regional politics.

The Iraqi leader, who last spring threatened to "burn half of Israel" with chemical weapons if the Jewish state launched an attack, also warned certain unnamed oil-producing rivals in a radio address Tuesday that "Iraqis will not forget the saying that cutting necks is better that cutting the means of living."

Kuwait fought back today with its own accusations against Baghdad, but also asked for Arab League mediation as Kuwaiti diplomats fanned out across the Middle East to seek backing against their belligerent northern neighbor.

In Washington, Defense Secretary Richard B. Cheney said today that the U.S. commitment to come to Kuwait's defense if it is attacked remains in force, but a former U.S. envoy in the Persian Gulf said the U.S. commitment has always been stated as protection "against the spillover from the Iran-Iraq war" and does not address aggression growing out of the current oil and territorial dispute between Baghdad and Kuwait.

Asked if a general U.S. pledge to come to Kuwait's aid still applied, Cheney said: "Those commitments haven't changed." He would not speculate, however, on how the United States might respond if Iraq moved to seize Kuwaiti territory. "We have got a lot of friends in the Persian Gulf," Cheney said, "nations we have historic relationships with . . . {and} obviously we take very seriously any threat that would put at risk U.S. interests or U.S. friends in the region." And he added, "We've demonstrated in recent years that we have, in fact, a good ability to respond and to do something about it."

To emphasize the U.S. commitment to the Arab gulf states, Cheney asserted that the large U.S. naval deployment to protect Kuwaiti oil tankers flying the American flag "was one of the more successful applications of military power in the post-war period."

Saddam Hussein's campaign of threat and intimidation has heightened tensions in the gulf to the highest level since a U.N.-sponsored cease-fire halted the bloody Iran-Iraq conflict two years ago. "This is not just someone wanting a leading role, but someone trying to establish paramountcy and dominance," said one U.S. gulf analyst in Washington. "This is what all small states in the region feared and thought wouldn't happen. Saddam does not like someone standing up to him, so he has resorted to outrageous accusations. He wants free rein -- a bigger quota for oil production, or to curtail production and push prices up. He is gambling."

In his radio speech Tuesday, Saddam Hussein accused unnamed gulf states of stabbing Iraq in the back with "a poison dagger" by exceeding their OPEC oil-production quotas, thus forcing down oil prices to favor the United States. He added that "if words fail to protect Iraqis, something effective must be done to return things to their natural course."

The next day, Iraqi media made public a letter from Foreign Minister Tariq Aziz to the Arab League in which he bitterly accused Kuwait by name of stealing $2.4 billion worth of Iraqi oil, building military installations on Iraqi territory and refusing to forego Iraq's wartime debts. Iraq's newspapers added fuel to the volatile atmosphere today, one with a giant headline reading "Kuwait Steals From Us," and another commenting in an editorial: "We have been too patient with the violations of Kuwait."

In its message today to the Arab League, Kuwait responded with a charge that "Iraq has a rich record in its violations of Kuwaiti territory, a record backed by facts." The Kuwaiti note asserted also that Iraq is digging oil wells on Kuwaiti territory and had refused repeatedly to settle a longstanding border dispute between the two countries.

Saudi Arabia's King Fahd telephoned Saddam Hussein and Kuwait's ruling emir, Sheik Jabir Ahmed Sabah, to cool emotions, and Arab League secretary general Chadli Klibi will fly to Kuwait Friday to attempt to mediate the dispute, news agencies reported.

But while Saddam Hussein's regional ambitions may play a central role in Iraq's latest saber-rattling, many Middle East experts say that growing difficulties in Iraq's hard-pressed economy may be the prime motive for the verbal assault on Kuwait, a fellow member of the 13-nation Organization of Petroleum Exporting Countries.

Iraq, which has the world's second-largest oil reserves, had been banking on high oil prices this year to finance its ambitious postwar reconstruction and military programs, and to pay off interest on an estimated $40 billion in war loans from Japan and West European countries.

At the moment, it is having trouble finding new sources of credit and is struggling to contain inflation and create jobs so that it can demobilize part of its armed forces, which remain at a wartime level of about 1 million, Baghdad-based diplomats have said.

But lower than expected world demand for oil, combined with a market glut -- partially generated by overproduction by Kuwait and the United Arab Emirates -- has caused a steep slide in OPEC oil prices from $21 a barrel last year to $16 currently. If prices do not rebound significantly, Iraq's "oil revenues, short of a miracle, are going to be extremely depressed," and this could spell disaster" for Baghdad in light of its development plans, said Keith McLachlan, an Iraqi expert at London's School of Oriental and African Studies. "I think this really has to be the motive pushing the Iraqis," McLachlan said, echoing assessments by other experts.

But Iraq's decision to make a public issue of its border dispute with Kuwait, which has been simmering in private, could cause unforeseen problems, McLachlan said. "The thing has begun because of oil and a revenue problem, but it might develop into something of a Frankenstein monster with a political dimension."

Saddam Hussein is not the first Iraqi ruler to make territorial threats against Kuwait, whose independence in 1961 was followed by an Iraqi claim of sovereignty over all Kuwaiti territory and oil wealth. At that time, Britain responded by landing troops in Kuwait and sending naval forces into the Persian Gulf until the Iraqis backed down.

Approval of the Iraqi leader's new status as president for life came during a three-day session of Iraq's 250-member assembly, which is dominated by Saddam Hussein's Baath Arab Party. Saddam Hussein, 54, had promised political reforms -- including a multi-party system, a free press and the first free elections since Iraq became a republic in 1958 -- but today's action indicated that the leadership has reneged on the pledge.

Staff writers Patrick E. Tyler and Nora Boustany contributed to this article in Washington.