Syria has accepted a peace plan by U.N. envoy Kofi Annan, which includes a cease-fire by Syrian forces and a daily two-hour halt to fighting to evacuate the injured, Annan's spokesman said Tuesday.

But there was no immediate end to the bloodshed as intense clashes between Syrian troops and rebel fighters spilled across the border into Lebanon on Tuesday and heavy gunfire slammed into the rural, sparsely populated frontier area, officials said.

Syrian troops did not physically cross the border, however, according to two Lebanese security officials, one from the police and another from the military. The fighting erupted in the Mashareaa al-Qaa area, on the Syrian side.

The U.N. says more than 8,000 people have been killed in Syria's yearlong uprising. There are concerns that the conflict could cause a regional conflagration that sucks in neighboring countries.

A diplomatic push to end the crisis has largely failed, but Ahmad Fawzi, a spokesman for Annan, said Tuesday that the Syrian government has accepted Annan's six-point plan to end the bloodshed.

Also Tuesday, President Bashar Assad visited Baba Amr, a former rebel stronghold in the key city of Homs that became a symbol of the uprising after a monthlong siege by government forces killed hundreds of people _ many of them civilians _ as troops pushed out rebel fighters.

Homs has been one of the cities hardest hit by the government crackdown on the uprising that began last March. Assad's forces overran the rebel-held Baba Amr on March 1 but faced resistance from other districts.

Assa's visit was reported on Syria's state-run news agency, SANA. There were no further details.

The violent conflict in Syria has posed a serious challenge to Assad, but neither side has shown any sign of giving in. The opposition, riven by differences, has failed to present a united front against Assad, which has added to the chaos.

Syrian opposition leaders were meeting in Istanbul on Tuesday in an attempt to resolve their differences and reassure international backers who are frustrated by the lack of cohesion.

The meeting comes ahead of an April 1 conference in Istanbul at which Turkey, the United States and their European and Arab partners will discuss ways to further isolate and pressure Assad, as well as measures to support the Syrian opposition. Some reports indicate that the debate among dozens of countries will include whether the opposition Syrian National Council and affiliated groups should be declared as the sole, legitimate representative of the Syrian people.

A Turkish official, speaking on condition of anonymity, said that "if the majority of participants choose that, we'll do that."