Armed clashes on the remote, disputed border between Cambodia and Thailand killed at least 12 people on Thursday, in a dramatic escalation of tensions that threatens to erupt into a broader conflict.

Cambodia is seeking to "internationalise the issue to serve its own political objectives", Thailand’s ambassador to the United Nations Cherdchai Chaivaivid told a closed-door UN Security Council meeting.

Cambodian rocket attacks led to 14 Thai civilian deaths on July 24. Thailand retaliated with fighter jet strikes on military targets.