Despite Iraq's daily claims of success in its war with Iran, evidence is mounting here that the Iraqi Army has been severely bloodied in recent weeks in trying to retake the Faw Peninsula at the head of the Persian Gulf.

Western military observers monitoring the 5 1/2-year-old war say they believe that the Iraqi Army has suffered close to 10,000 dead and wounded since Iran overran Faw on Feb. 9 in a surprise amphibious and helicopter-borne attack. The marshy peninsula was the site of Iraq's main oil-loading port before the war.

As a result of the casualties, the western observers say, the government of Iraqi President Saddam Hussein apparently has decided not to attempt to retake Faw because the cost would be too great, politically and militarily.

At the same time, Iraq also has to deal with an Iranian breakthrough on the border in the Kurdistan region in the north and a new Iranian offensive in the Howeizeh marshes northeast of Basra.

Besides the reported 10,000 casualties -- almost twice as many as Iraq suffered during Iran's last major offensive, in the Howeizeh marshes last year -- Iran also apparently has inflicted a severe defeat on Iraq's crack Republican Guards, the nation's strategic reserve that was sent in to lead the counterattack.

In the words of one senior western diplomat here who, like all other foreign observers interviewed, refused to be identified, this 20,000- strong unit has been "mauled."

These accounts conflict sharply with the military communiques that the Iraqi government issues nightly, which remain euphoric.

A month after Iran caught Iraq off guard in the Faw Peninsula south of Basra, Iraq's second city and its major outlet to the gulf before the war, Iraq talks nightly of moving from "victory to victory" against the Persian enemy occupying its strategic territory.

"Seventh Army presses on, gains more ground," said one communique last week. Another mentioned Iraq wiping out "nine enemy divisions."

Whatever real Iraqi victories there have been -- and western military analysts here dispute the existence of any -- they have been costly.

Facts and figures are hard to come by in this secretive country, but evidence of the Republican Guards' suffering can be read between the lines of a speech by Saddam Hussein three days after the Iranian invasion of Faw, when he singled out the guards to praise their "martyrdom" and "heroism."

Since that speech, there has been no public reference to their role, which, diplomats here said, seems to confirm private reports that they suffered so many casualties in the first days of the counterattack that they have been withdrawn from the line to regroup.

Persistent reports that a new mass recruiting drive for the Republican Guards has been launched tend to confirm that the ranks of this elite force have been depleted in recent fighting.

An indication that casualties are high is seen in the action of Iraqi security agents manning road blocks on the Basra-Baghdad road. They have begun ordering empty taxicabs on the road to return to Basra to pick up flag-draped coffins for transport north. The roads north of Basra are full of taxis with coffins on their roof racks, flags flapping, as they stream toward Baghdad and other cities far from the southern front.

Foreign diplomats here say that almost all of their local employes seem to have lost someone in the fighting; some have lost two or three relatives over the course of the war.

In the villages around Baghdad, new flags of mourning fly over many modest homes, although no such flags are evident in Baghdad -- because, some European diplomats say, the ruling Baath Party has passed the word that such visible mourning signs should not be displayed where they could easily be seen by foreigners.

Nevertheless, foreigners visiting hospitals say they are crowded to the point of overflowing and western embassies have heard reports that almost nightly for the past three weeks, at least two trains have arrived from Basra full of wounded.

Foreign workers say there is such a need for blood for transfusions that they have been forced by Iraqis to donate blood or lose their lucrative jobs here.

"We were told we simply had to have another physical," said one of the thousands of Filipino women working in Iraq's tourist hotels. "Then they jabbed us with a needle and siphoned off a pint of blood."

There are other signs that Iraq is hurting. Like Iran, it has built up a force of a million armed men to fight in this war, but it recently has resorted to forced recruiting to fill the ranks left vacant in the continuing struggle for Faw.

Although officially the draft age remains 18, westerners in touch with Iraqi families have recently heard of cases where 16-year-olds were called into the Army.

Ten days ago, the entire staff of 450 foreign and local employes of the Meridien Hotel here, run by Air France, were called together by Iraqi recruiters and offered money and benefits to join the Army. All refused, according to a European familiar with the incident, although at least three Sudanese employes whose residence papers were found to be out of order reportedly were ordered into the Popular Army, Iraq's 450,000-strong home guard.

"If you ask me, they are scraping the bottom of the barrel for new recruits these days," a foreign military attache said. "I think we are near the so-called 'red line' on casualties beyond which the government feels it cannot go without facing serious problems politically at home."

No one denies that Iran has probably suffered greater casualties on Faw than has Iraq, especially given Iraq's superiority in air and artillery. But throughout the war the Iranians, backed by the zealousness of their Shiite Moslem religion, have proven more willing -- and able -- to afford high casualties because of their troops' higher motivation and their country's three-to-one population advantage over Iraq.

Having pushed an estimated 30,000 troops into Faw over pontoon bridges and on ferries under cover of darkness, Iran is now dug in around the abandoned town of Faw, under daily heavy fire from Iraqi artillery and helicopter gunships.

Sources with access to U.S. satellite pictures of the battlefield confirm impressions received in visits to command posts near Iraqi front lines that Iraq's Army is not advancing as communiques claim. Instead it seems to be digging in with artillery and simply bombarding the enemy, to contain it, thus avoiding the additional high casualties that would result from an attempt to use infantry to push the Iranians back across the Shatt al Arab.

"I think the decision has already been made that it is simply too costly in terms of casualties to push the Iranians out of Faw," one senior foreign military observer here said. "The betting here is that they will simply seal the area off with troops, put artillery in it, and rationalize the fact that Iran has found a new toe-hold in Iraqi territory."