China is intensifying its efforts to expand its influence in the Pacific and stymie a $500 million treaty deal between Australia and Vanuatu as the Albanese government forges ahead with plans to sign a sweeping security pact with Fiji.

Foreign Minister Penny Wong and Pacific Minister Pat Conroy travelled to Fiji on Tuesday to drive forward negotiations on the Vuvale Union, a treaty-level agreement that would deepen ties between Australia and one of the Pacific’s most powerful countries.

The progress on a new treaty with Fiji stands in stark contrast to efforts to achieve a breakthrough on a stalled pact with Vanuatu, a nation that is a key geopolitical battleground between Australia and China in the Pacific.

Prime Minister Anthony Albanese travelled to Vanuatu last year but left without signing a 10-year security pact.…