As tensions in the Pacific continue to simmer, US marines are ready to deploy from the Northern Territory

The US Marine Corp says this year's deployment to Darwin is the most "combat-credible" group sent yet, as the troops complete a week of intense training on the remote Tiwi Islands.

The Australian Strategic Policy Institute's Dr John Coyne said the increased US presence in northern Australia signalled the region's strategic importance to both countries.

"There's clear evidence the US government is going to invest more in ensuring that supply chains [and] defence logistics facilities are present in northern Australia and ready to support a range of contingencies," he said.

"Forward deployment in Darwin and northern Australia really provides proximity to the region, it provides a capacity [for the US] to leapfrog operations," Dr Coyne said.

"It provides the US military with a forward operating base from which it can launch into the region."