Thailand has rejected mediation efforts from third countries to end the ongoing conflict with Cambodia, insisting that Phnom Penh cease attacks and resolve the situation only through bilateral talks, its foreign ministry said on Friday, Reuters reported.

Simmering border tensions between Thailand and Cambodia have flared into open hostilities at multiple locations along the frontline, with exchanges of artillery for a second straight day.

At least 16 people, most of them Thai civilians, have died so far in the heaviest fighting between the Southeast Asian neighbours in over a decade.

The United States, China and Malaysia, which is the current chair of the ASEAN regional bloc, have offered to facilitate dialogue but Bangkok is seeking a bilateral solution to the conflict, Thai foreign ministry spokesperson Nikorndej Balankura told Reuters.