BEIJING–Another Chinese oil rig is set to arrive Friday in the South China Sea, authorities said, as Beijing and Hanoi trade accusations over an increasingly heated territorial row.

The move marks a fresh escalation of the dispute, which has seen a wave of deadly anti-Chinese riots in Vietnam as well as accusations from both sides of ramming by the other’s vessels following China’s dispatch seven weeks ago of a rig into waters Hanoi claims.

Talks in Hanoi between Chinese State Councillor Yang Jiechi and Vietnamese Foreign Minister and Prime Minister Nguyen Tan Dung over the dispute ended in deadlock on Wednesday.