The defence ministers of South Korea and China have agreed to develop their security ties to ensure stability in north-east Asia, the latest indication that Washington’s long-standing alliances in the region are fraying.

On the sidelines of regional security talks in Bangkok on Sunday, Jeong Kyeong-doo, the South Korean minister of defence, and his Chinese counterpart, Wei Fenghe, agreed to set up more military hotlines and to push ahead with a visit by Mr Jeong to China next year to “foster bilateral exchanges and cooperation in defence”, South Korea’s defence ministry said.

Seoul’s announcement coincided with growing resentment at the $5 billion (£3.9bn) annual fee that Washington is demanding to keep 28,500 US troops in South Korea.

That figure is a sharp increase from the $923 million that Seoul paid this year, which was an 8 per cent increase on the previous year.