BEIRUT - The leader of the rebel Free Syrian Army (FSA) said on Sunday a peace plan put forward by international mediator Kofi Annan was bound to fail because Syria's government would not implement it.Riad al-Asaad added his group had not been asked to deliver written guarantees to end the violence in Syria - apparently contradicting Damascus which on Sunday said it had demanded the written pledge as a condition for the withdrawal of its troops."The regime will not implement this plan. This plan will fail," he told Reuters by phone from Turkey. The rebels had already given a verbal promise to stop fighting if the government did the same. "We have given our word that if the regime commits to the plan then we will too. We are honest."The plan, drawn up by UN-Arab League envoy Kofi Annan, requires Syrian President Bashar Assad to "begin pullback of military concentrations in and around population centers" by Tuesday for a truce to start 48 hours later.Earlier Sunday Al Jazeera had reported that a senior general in the Free Syria Army had rejected Syria's demand for written guarantees that insurgents will stop fighting before Syria pulls troops under the terms of a peace plan. Escalating violence has already raised questions over the ceasefire, and the dispute regarding Syria's request only puts the likely success of the wobbly truce further into doubt.Opposition activists said dozens of people were killed and wounded on Sunday when Syrian President Bashar Assad's loyalists shelled a rebellious area near the border with Turkey.UN-Arab League envoy Kofi Annan, seeking to end the conflict that has killed more than 9,000 people in the past year, said the latest bloodshed violated the guarantees he had been given and urged Damascus to keep its promises. While emphasizing that would happen, Foreign Ministry spokesman Jihad Makdissi said in a statement that Syria also wanted the written guarantees. Syria also sought guarantees that Qatar, Saudi Arabia and Turkey - outspoken in criticizing Assad - would not fund the armed groups.Annan made no specific reference to the new Syrian demands in a statement from his office in Geneva. He expressed shock at the "surge in violence and atrocities." Each side has accused the other of intensifying assaults in the run-up to the truce. "As we get closer to the Tuesday 10 April deadline, I remind the Syrian government of the need for full implementation of its commitments and stress that the present escalation of violence is unacceptable," he said.