The Syrian port of Tartus on the Mediterranean Sea has been busy lately with comings and goings of Soviet warships, eager to get as close as possible to the Iraqi crisis without getting in it.

The flurry of activity underscores a secret agreement between the Soviet Union and Syria to turn part of the port at Tartus into a Soviet naval base, which is off-limits to Syrians.

The provocation by Iraqi strongman Saddam Hussein has left the Soviets in a quandary about how to use their port at Tartus. The Soviet Union voted for the U.N. embargo against Iraq, but has not pledged its ships to enforce that embargo.

Central Intelligence Agency sources tell us that the Soviets don't want to appear aggressive in the region, particularly since Iraq has been their ally for many years and they hope the Iraqis will let bygones be bygones when the crisis is over.

But CIA reports say there has been a bumper crop of Soviet naval ships in the Mediterranean, stopping at Tartus to refuel and linger close to the action.

The Soviets have another reason to stick close to Tartus. They want to encourage a closer relationship with Syrian leader Hafez Assad, a longtime enemy of Saddam. Syria has been the Soviet Union's closest ally in the Middle East, but Assad had come to doubt Moscow's fidelity.

Assad has seen the number of Soviet military advisers in Syria drop from a high of 6,000 in 1982 to about 2,500 currently. So he flew to Moscow in April for a three-hour private session with Mikhail Gorbachev.

Gorbachev said he was as friendly as ever with Syria, but couldn't afford to subsidize Syria's insatiable appetite for weapons and didn't see the need for Syria to reach strategic parity with Israel. Classified CIA reports show that Syria already owes the Soviet Union $15 billion for weaponry.

To satisfy Assad, Gorbachev said he would rush an order of Soviet Su-24 fighter planes, which would be able to drop Syrian chemical weapons on Israel.

The Soviets are willing to risk an escalation of tensions by giving Syria the planes because the Syrians give access to Tartus in return. Ever since Egypt kicked the Soviets out of their last Mediterranean naval base at Alexandria in 1976, the Soviets have been desperate to find and keep another.

They were so eager, our sources say, that they have forgiven more than $1 billion in Syria's military debt. The Soviet base at Tartus is not discussed in the Syrian press and treated as a secret by the government. Syrian officials are allowed in only with special passes.

Several Soviet ships, including a submarine tender, are stationed there permanently and the base may become the largest permanent Soviet naval base outside of the U.S.S.R.

The visiting warships this summer, including an aircraft carrier, are from the Soviet Black Sea Fleet and the submarines are from the Northern Fleet.