The United Nations-Arab League joint envoy Kofi Annan is due to visit Syria on Monday for talks with government officials on the shaky implementation of his peace plan, diplomatic sources here said Friday. Annan is also expected to meet with opposition politicians inside Syria, the sources said . A key component of Annan\'s plan to end 14 months of bloodshed in Syria, a ceasefire, has been repeatedly violated since it went into effect on April 12. The presence of some 250 United Nations monitors in Syria to supervise the truce has not stopped the violence, which has intensified in some dissident areas, say observers. \"Annan\'s plan is in jeopardy,\" said a Western diplomat based in Beirut, noting that the prospects of a diplomatic solution to Syria\'s conflict appeared \"weak.\"