China claims Taiwan is part of its territory and has threatened to use force to bring the island under its control, stepping up military pressure in recent years with drills staged around the island.

The intelligence community "assesses that Chinese leaders do not currently plan to execute an invasion of Taiwan in 2027, nor do they have a fixed timeline for achieving unification," said its Annual Threat Assessment report.

Last year US officials at the Department of Defense had flagged 2027 as a possible timeline for an attack.

But the intelligence community offered a more measured analysis of the situation.

"In 2026, Beijing probably will continue seeking to set the conditions for eventual unification with Taiwan short of conflict," the report said.

But it cautioned that Chinese officials recognize that an amphibious invasion of Taiwan "would be extremely challenging and carry a high risk of failure, especially in the event of US intervention."

The report's authors said China publicly insists "unification with Taiwan is required to achieve its goal of 'national rejuvenation' by 2049", a much longer potential timeline to achieve its goals.

Beijing would consider a range of factors in any decision to invade Taiwan, it said, including its military readiness, the island's politics and whether or not Washington would intervene on Taiwan's behalf.

Washington does not officially recognize Taiwan, but is the island territory's main military backer -- although the tone of that support has softened slightly under US President Donald Trump.