Fighting on the Thai-Cambodian border extended into a third day and new flashpoints emerged on Saturday as both sides said they had acted in self-defence in the border dispute and called on the other to cease fighting and start negotiations.

Cambodia wants an "immediate ceasefire" with Thailand, the country's envoy to the United Nations said Friday, after the neighbors traded deadly strikes for a second day, with Bangkok also signaling an openness to talks.

Thailand and Cambodia pounded each other with heavy artillery fire for a third day on Saturday, as a border conflict that killed at least 33 people and displaced more than 150,000 from their homes spread across the frontier.

Skirmishes have continued across multiple points on the border, with reports of mortar fire, small arms exchanges, and new troop deployments

Death toll climbs to 33, including 5 Cambodian soldiers, 6 Thai soldiers, with dozens injured across disputed border - Anadolu Ajansı

Cambodia's prime minister Hun Manet said on Friday that he had supported a proposal by the Malaysian premier for a ceasefire with Thailand, which later withdrew its initial backing of the plan.

Thailand's acting Prime Minister Phumtham Wechayachai on Friday blamed Cambodia for initiating the latest armed conflict by using "military force first," while imposing martial law in border provinces.