A Donald Trump tweet that upped US/China tensions and sent markets into a spin this week could be a sign that the trade war is nearing resolution, says one expert visiting New Zealand this week.

The US had started playing hardball because it "realises that things are reaching the end of the negotiation phase", said Duncan Innes-Ker, the Economist Intelligence Unit's regional director of Asia and Australia.

"It wants to bring China across the line and make sure that it gets those last concessions that they've been talking about for the last few months," said Innes-Ker, who was in Auckland