Relations between Taiwan and the United States are "stronger than ever", an envoy for President Joe Biden said Thursday during a visit to the democratic island as it faces increasingly hostile moves by China.
Former senator Christopher Dodd and former deputy secretaries of state Richard Armitage and James Steinberg were asked by Biden to travel to Taipei this week, in the first such delegation since the new US administration came to power.
"I can say with confidence the US partnership with Taiwan is stronger than ever," Dodd said as he met with President Tsai Ing-wen on Thursday morning.
"You will find the Biden administration, madam president, to be a reliable, trusted friend," he added.
"I'm confident this administration will help you expand your international space, support your investment in self defence."
Taiwan's 23 million people live under the constant threat of invasion by authoritarian China, which uses diplomatic, economic and military pressure to keep the island isolated on the world stage.
Beijing claims Taiwan as its own territory and has vowed to one day seize it.
China's sabre-rattling has increased considerably over the past year, with fighter jets and nuclear-capable bombers breaching Taiwan's air defence zone on a near-daily basis.
"Recently China has frequently dispatched military vessels and aircraft to carry out maneuvers in waters and airspace surrounding Taiwan," Tsai told Dodd.
"These actions alter the status quo in the Indo Pacific and threaten regional peace and stability."
A record 25 Chinese military jets and bombers breached Taiwan's defence zone on Monday just ahead of the visit, which Beijing condemned.
The exercises have rattled senior US military figures who have publicly warned policy makers in recent weeks that Beijing may be considering an invasion.
Analysts are divided on how likely such a drastic move is and warn any invasion could prove enormously costly to China, despite its military might.
Washington has diplomatically recognised Beijing over Taiwan since 1979.
But it maintains relations with Taipei and is bound by an act of Congress to sell the island defensive weapons. It also opposes any attempt by China to change Taiwan's future by force.
This week's delegation comes on the 42nd anniversary of that legislation -- the Taiwan Relations Act -- which Biden signed when he was a young senator.
It also comes after the State Department said on Friday it was issuing new guidelines to allow US officials to meet more easily with Taiwanese counterparts.
Biden's predecessor Donald Trump ramped up contacts and visits to Taiwan by US officials as relations between Washington and Beijing plunged over a host of issues.
The president has made clear he wishes to cooperate with China on common causes such as climate change.
But concerns about China under President Xi Jinping have become a rare area of bipartisan consensus in Washington, and Biden has maintained a tough line with Beijing over its human rights record and threats towards Taiwan.