Taiwan urged the United States Sunday to continue arming it with defensive weapons as it kept a wary eye on the first summit between US President Barack Obama and his Chinese counterpart Xi Jinping.

During the meeting in California, the Chinese side had asked the US to end its arms sales to Taiwan, which Beijing sees as part of its territory.

"We urge the United States to continue selling defensive weapons to the Republic of China (Taiwan) according to the Taiwan Relations Act and the Six Assurances the United States promised to Taiwan," Taiwan's defence ministry spokesman David Lo told reporters.

Washington switched diplomatic recognition from Taipei to Beijing in 1979. But it has continued to arm the island in accordance with the Taiwan Relations Act approved by Congress the same year.

In 1982 the Reagan administration orally delivered "Six Assurances" to Taipei, promising not to set a date to end arms sales to Taiwan, nor to hold prior consultations with China on such sales.

Taiwan's foreign ministry has set up a group to monitor Xi's visit to the United States, officials said.

Ties across the Taiwan Straits have improved markedly since Ma Ying-jeou of Taiwan's China-friendly Kuomintang party came to power in 2008. He was re-elected in January 2012.

But Beijing has still refused to renounce the possible use of force to reunify with Taiwan, even though the island has ruled itself since the end of a civil war on the mainland in 1949.

Taiwan has continued to seek advanced weapons, largely from the United States.