The United States has signed a security pact with Papua New Guinea in an apparent bid to counter China's growing influence in the South Pacific region.

US Secretary of State Antony Blinken arrived in the island nation on Monday for talks with Prime Minister James Marape, following the G7 summit in Hiroshima, Japan.

Blinken signed the pact aimed at making it easier for the US military to train with the forces of Papua New Guinea.

Blinken also met with leaders of the Pacific Islands Forum. The 18-member forum includes island states in the Pacific, as well as Australia and other countries.

The US government plans to invite leaders in the region to Washington by the end of the year for talks centered around climate change and maritime surveillance.

Blinken was sent to Papua New Guinea in place of President Joe Biden, who was initially due to make a stopover there on his way home from Hiroshima. But Biden called off the plan due to a standoff in Washington over raising the US debt ceiling.

The move to increase US involvement in the Pacific island nation is seen as an attempt by the Biden administration to counter China's growing influence in the region.