Israel will wait "a few weeks" to see if Syria becomes willing to withdraw its troops from Lebanon and then will consider a redeployment of its own forces there in the hope this will increase pressure on Syria from other Arab countries, a senior Israeli official said today.

The official, who asked not to be identified and who is familiar with all aspects of the Lebanon troop withdrawal negotiations, outlined the Israeli strategy in the next stage of the struggle to achieve the withdrawal of all foreign forces from Lebanon.

He said the more than 30-page Israeli-Lebanese accord should be signed next week by David Kimche, the director general of the Israeli Foreign Ministry and head of the Israeli negotiating team, and Antoine Fattal, the chief Lebanese negotiator.

It will then be a matter of waiting for Syria to soften its opposition to the agreement, the official said, adding that while Israel has not set a time limit it will not "wait indefinitely."

The official indicated that the Israelis, and presumably the United States as well, do not consider Syria's initial rejection of the troop withdrawal agreement the final word. Rather, he suggested that Syrian President Hafez Assad will seek to win political and financial gains in the weeks ahead before finally agreeing to a Syrian and Palestinian withdrawal from Lebanon.

"I have little doubt that he Assad will play this to the brink," the Israeli official said. "He will play brinksmanship, and Assad has shown in the past he is very good at this."

The official added, "On balance I think the Syrians will be willing to withdraw, but the price may be so high it won't work out. I think they will ask a very high price."

The official also warned that a "game of brinksmanship" by Assad "could be very dangerous" given the explosive situation in Lebanon, but said Israel "will do everything we can to prevent a military confrontation with Syria."

The Syrians, with a massive infusion of Soviet equipment and, according to Israeli estimates, the help of more than 4,000 Soviet advisers, have beefed up their forces in Lebanon's Bekaa Valley and in Syria itself. According to the Israeli official, the Syrians now have about 50,000 troops in Lebanon, more than three times the estimated Israeli troop strength of 15,000. These figures differ markedly from widely accepted recent official and semiofficial reports that place Syrian troop strength in Lebanon at 40,000 and Israeli at 30,000.

But despite predictions of an imminent Israeli attack being voiced in Damascus and Moscow and some war jitters here, officials appear to view the Syrian rhetoric and military buildup largely as part of a pyschological tug of war.

The Israelis clearly see a redeployment of their forces, possibly to positions south of the Awali River, as one option open to them in the psychological and diplomatic fencing with the Syrians.

For the Israelis, such a move would have the advantage of putting their Army in a stronger defensive position, with less chance of Israeli soldiers being injured as a result of fighting between rival Lebanese Christian and Druze factions in the Chouf mountains. It could also easily be interpreted as the beginning of a de facto partition of Lebanon between Israel and Syria, a development the Israelis see as increasing Arab pressure on Syria to agree to withdraw to get the Israelis out of Lebanon.

"Other Arab countries have a great interest in the return of stability to Lebanon," the Israeli official said. "They will see Israel redeploying because of Syria. The onus will be entirely on Syria."

Moreover, he argued that if Syria continues to refuse to withdraw its forces from Lebanon, it will risk isolation from more moderate Arab countries and the appearance that it is a "lackey" of the Soviet Union while still allowing Israeli forces in Lebanon to be within easy striking distance of Damascus.

The official said the "clarifications" the Israeli Cabinet is seeking on the troop withdrawal accord have not been completed, but added that these "are not necessarily of a dramatic nature."

The official also predicted a "dramatic improvement" in U.S.-Israeli relations as a result of the troop withdrawal agreement and indicated that this expectation was a major reason Israel showed "a great deal of flexibility" during Secretary of State George P. Shultz's shuttle mission last week that nailed down the final details of the accord.

He said Shultz put no pressure on Israel but that the Israelis recognized the high stakes the Reagan administration had in a successful conclusion of the secretary's mission.

"We did not want to send him back empty-handed," the official said.