Syrian forces have fired at the refugee camps across the border into Turkey killing at least two and injuring 15 refugees. The act is seen as a blatant violation of the international appeal on ending violence in Syria.

With the Tuesday deadline for a ceasefire in Syria just hours away, the peace deal teetered on the verge of collapse. Both the Assad regime and the rebels dug their heels in.

While the regime sought written guarantees from the rebels that they would lay down arms, the commander of the rebel Free Syrian Army, Riad al-Asaad said they would do no such thing as they did not recognise the discredited dispensation in Syria, according to the Press Association.

As the Kofi Annan-brokered peace push hit a logjam, Syrian Foreign Minister Walid al-Moualem was expected to arrive in Moscow on Monday and meet his Russian counterpart on Tuesday, the deadline for Syrian government forces to withdraw from cities and towns, Reuters reported.

The Syrian foreign ministry believes that without a written guarantee from the rebels, the government would only be giving time for the rebels to re-arm and reorganise themselves.

"To say that Syria will pull back its forces from towns on April 10 is inaccurate, Kofi Annan having not yet presented written guarantees on the acceptance by armed terrorist groups of a halt to all violence," the BBC reported the Syrian foreign ministry spokesperson as saying.

Rebel leaders are of the opinion that the latest demands by the Syrian authorities are a ploy to scuttle the peace plan.

Though the rebels are willing to go by the UN-Arab League truce, they are not ready for a direct deal with the Assad regime as the government troops continue their attack on civilians.

"We will present our guarantees and our commitments to the international community, but not to this (Syrian) regime," AFP quoted the Free Syrian Army's Col Riyad al-Asaad as saying.

Kofi Annan called for an immediate end to violence in Syria and appealed to the Assad regime to honour its commitments.

"This is a time when we must all urgently work towards a full cessation of hostilities, providing the space for humanitarian access and creating the conditions for a political process," the BBC quoted Annan as saying.

Violence has spiked as the date for the ceasefire nears and images coming out of Syria showed smoke emanating from Homs buildings.

According to CNN, the rebels and Syrian forces clashed near the Turkish border. Quoting the opposition Syrian Observatory for Human Rights, it said Six Syrian customs and security members were killed.

CNN also cited a report released by Human Rights Watch which says that Syrian security forces have summarily executed more than 100 civilians in recent days.