The State Department said Friday it will make it easier for US officials to meet Taiwanese representatives, defying pressure from China at a time of high tensions.
The United States still considers Beijing as China's legitimate government, consistent with its switch of recognition in 1979, but will do away with some of the convoluted rules that restricted dealings with Taiwan including in-person meetings.
The updated guidance "underscores Taiwan is a vibrant democracy and an important security and economic partner that is also a force for good in the international community," State Department spokesman Ned Price said.
"These new guidelines liberalize guidance on contacts with Taiwan, consistent with our unofficial relations," he said in a statement.
The move by President Joe Biden's administration formalizes increasingly vocal US support for Taiwan, a self-governing democracy, and comes in response to an act of Congress that required a review.
Taiwan's mission in Washington -- officially called the "Taipei Economic and Cultural Representative Office in the United States", rather than an embassy -- welcomed the new guidelines, saying they reflected a bipartisan consensus for closer relations.
"Taiwan and the US share a deep and abiding partnership based on our common values and joint interests," it said, pointing to cooperation on global health, space, trade and democracy promotion.
Former secretary of state Mike Pompeo, a staunch critic of Beijing, in his last days in office said he was getting rid of previous guidelines on dealing with Taiwan but not issue new ones, drawing confusion in some quarters on what had changed.
- Open meetings -
Under the guidelines issued by the Biden administration, US officials will be allowed to invite Taiwanese representatives into government buildings in Washington or attend working-level meetings at the Taiwanese mission, both of which were earlier prohibited, a State Department official said.
The United States has already begun allowing open interactions with Taiwanese diplomats since Pompeo ended earlier guidance.
The Biden administration last month sent the US ambassador to Palau on a visit to Taiwan to accompany the president of the island nation -- one of a dwindling number of countries that recognize Taipei.
Similarly, the acting US ambassador in Japan in March tweeted a picture of himself meeting at his official residence with his Taiwanese counterpart -- the type of day-to-day diplomacy that is usually a non-event but which Washington had previously shied away from with Taiwan for fear of upsetting Beijing.
The new guidelines are also expected to relax the strict protocol on whether junior US officials can appear at Twin Oaks, the lush, forested residence of Taiwan's envoy in Washington.
Twin Oaks events routinely draw a who's who of US lawmakers and former officials but sitting government employees are careful to steer clear.
Senior US officials have periodically visited Taiwan, with former president Donald Trump's health secretary traveling in August, although Washington has remained careful not to anger China by sending cabinet members involved in national security.
China considers Taiwan, where the mainland's defeated nationalists fled in 1949 after losing the civil war, to be a territory awaiting reunification, by force if necessary.
Taiwan in recent days reported growing air incursions by Beijing. Joseph Wu, Taiwan's foreign minister, has called the approach "self-defeating."
The United States has voiced concern about the Chinese moves and warned against any coercion against Taiwan.
Under the Taiwan Relations Act approved by Congress when the United States switched recognition, Washington is required to provide Taiwan with weapons for its self-defense.
The easing of rules comes amid soaring tensions between the United States and China on multiple fronts.
The United States also accuses China of rampant intellectual property theft and of carrying out genocide in the western region of Xinjiang, where some one million Uyghurs and other mostly Muslim people are believed to have been rounded up in camps.