Josh Frydenberg is being warned that massive federal government debt from emergency pandemic spending could double in coming decades as borrowing costs rise and spending costs blow out.

Tensions between the two countries are still high, and Beijing still has not ended the diplomatic freeze on top-level meetings with Chinese leaders.

The Reserve Bank is holding the line on low interest rates for years to come, but some economists warn the risks of an inflation "rebirth" are rising, an issue the US central bank will be discussing this week.

The deputy leader of the Nationals says the party has struck a deal to allow more foreign workers into Australia to work on farms, hinting that an agriculture-specific visa could soon be announced.

The works will help counter China's increasing reach into the region and will be completed with the help of the US navy, the head of Papua New Guinea's Defence Force says.