BEIRUT (AP) — The UN insists a fragile truce it brokered in Syria is holding, even though regime forces have been hammering the rebellious city of Homs with artillery for days.

It’s a sign of the leeway the international community seems willing to give President Bashar Assad in hopes of forcing him into the next stage of special envoy Kofi Annan’s peace plan — talks with opponents who demand his removal.

Assad has made it brutally clear that he won’t step aside, trying to snuff out a 13-month uprising with tank fire and mass arrests. Even though he ostensibly accepted Annan’s plan, he’s likely to wriggle out of it since he seems largely insulated from pressure.

He does not face a threat of Western military intervention. Poorly armed rebel fighters don’t pose a danger to his rule. And Assad has the backing of Russia, China and Iran, along with key groups at home.

Some even argue the Annan plan has actually allowed Assad to strengthen his hold on the country of 22 million.

“There is nothing to suggest that there is light at the end of the tunnel here,” said Shadi Hamid of the Brookings Doha Center, a Gulf-based think tank. “If the end game is the fall of the Assad regime, I don’t think we are any closer to the end game.”

From the time the April 12 cease-fire deadline was announced, the regime escalated blanket shelling attacks on rebel-held neighborhoods, killing dozens every day in what the opposition described as a frenzied last-minute rush to crush the uprising.

Yet the plan by Annan, the joint UN-Arab League emissary, is the only one a deadlocked international community could rally behind and is seen as the only practical way forward.

The West is “half-heartedly supporting the Annan plan although it expects it to fail, because it is even more hesitant at the idea of getting sucked into an armed confrontation,” said Peter Harling of the International Crisis Group think tank.

Syria’s allies, meanwhile, back the initiative because, unlike an Arab League plan earlier this year, it does not require Assad to step down ahead of transition talks.

Still, even Annan demands that Assad eventually “address the legitimate aspirations and concerns of the Syrian people” in talks with the opposition.

The behavior of the regime in the past few days suggests the plan is likely to unravel well before any political talks could begin.

Since a truce formally took effect Thursday, Syria has violated key provisions. Tanks, troops and widely feared plainclothes security agents continue to patrol the streets to deter anti-regime protests, despite Annan’s demand that the army pull back to its bases.

And while there’s been a sharp drop in violence since last week, the regime resumed its assault on rebellious Homs, Syria’s third-largest city, over the weekend, after only a brief lull.

U.N. chief Ban Ki-moon hinted Monday he’s ready to overlook Assad’s transgressions for now. He said the truce is “very fragile” but essential for getting to political negotiations, suggesting Ban is willing to stretch the definition of a cease-fire to salvage Annan’s plan.

It’s not clear if Ban will call out Assad on truce violations once a full contingent of up to 250 UN monitors has been deployed. So far, only an advance team of six is on the ground.

Annan has been intentionally vague about the terms of political talks since gaps are vast and neither side even recognizes the other. The regime portrays its opponents as thugs and terrorists, while the Syrian National Council, the main opposition group, says there’s no point talking to Assad.

Political leaders of the opposition say they’re willing to let Annan’s plan play out even though they believe Assad has no intention of heeding it.

If Assad keeps violating the truce, it will sharpen the message that he can’t be reasoned with and that the world needs to take more forceful action, said Louay Safi, the Syrian National Council’s chief strategist in exile.

But if, against all odds, the regime were to scale back violence, it could quickly lose control as peaceful protesters flood the streets, Safi said.

“Popular pressure, the atmosphere, will bring down the regime and probably those in control now will have to negotiate their way out,” he said.

Others say it’s unlikely Assad will let things get this far.

During last Friday’s anti-regime marches, the first since the truce, troops opened fire on demonstrators in some areas, killing at least six, but stood by in others. Activists reported a much larger turnout than in previous months, when an intense clampdown reduced the crowd sizes, but said an intimidating troop presence still kept many Assad opponents off the streets.

Analysts say that in the end, only two things can force Assad’s hand — a real military threat from abroad or at home, or a change in Russia’s position, neither of them likely to happen soon.

Economic sanctions have started to bite, but experts say regimes can survive them for months or years, and Syria’s allies, including oil-rich Venezuela, can try to soften the blow.

Russia and fellow UN Security Council member China have effectively shielded Assad from international condemnation so far. Moscow’s nudging was key to getting Assad to accept the Annan plan, but it’s not clear how far Russia would go in demanding compliance.

While Russian leaders may be uneasy about the regime’s brutality — more than 9,000 people are said to have been killed since March 2011 — they do not have compelling reasons yet to dump Assad, said Asli Bali, a law professor at the University of California at Los Angeles.

Russia and Iran will only pressure Syria if they get something in return, Bali said. Russia would likely seek guaranteed access to Syria’s Mediterranean ports, while Iran could demand an easing of sanctions imposed to halt its suspected nuclear weapons program, she said.

“Absent some kind of grand bargain to enable negotiations to move toward a political transition, there is no reason to expect the cease-fire to hold for long or for a transition to follow,” Bali said.

Expectations should be kept low, cautioned Harling, the Crisis Group analyst.

The Annan plan “will definitely not bring all violence to an end. It won’t topple the regime,” he said. “The immediate, the urgent aim should be to de-escalate the violence which has crossed very dangerous thresholds.”