The US and Taiwanese vice-presidents had a brief conversation on Thursday at the inauguration of the new Honduran president, a rare encounter that is highly symbolic and likely to add to Beijing's tensions with Washington.

The United States, like most countries, has no formal diplomatic relations with Taiwan, though its strong support for the island both politically and through arms sales is one of the main sources of Sino-US friction.

US Vice-President Kamala Harris said she spoke with her Taiwanese counterpart, William Lai, in Honduras about their shared interest in Central America and the US government's "root causes" strategy to curb migration.

"The brief conversation that we had was really about...