The State Department informed Congress on Tuesday of the $80 million package, which is small compared with recent sales to Taiwan but marks the first assistance to Taipei under the Foreign Military Financing program, which generally involves grants or loans to sovereign countries.

The move is sure to anger China. For five decades, the United States has officially recognized only Beijing although Congress, under the Taiwan Relations Act, requires the supply of weapons to the self-governing democracy for its defense.

Successive US administrations have done so through sales rather than direct aid to Taiwan, with formal statements speaking in the tone of business transactions with the island's de-facto embassy in Washington.

The State Department insisted that the first-ever aid under the program did not imply any recognition of sovereignty of Taiwan.

"Consistent with the Taiwan Relations Act and our longstanding One China policy, which has not changed, the United States makes available to Taiwan defense articles and services necessary to enable it to maintain a sufficient self-defense capability," a State Department spokesperson said.

"The United States has an abiding interest in peace and stability in the Taiwan Strait, which is critical to regional and global security and prosperity."

Taiwan's defense ministry expressed gratitude. "The aid will help in regional peace and stability," it said in a short statement.

The State Department did not formally announce the aid or give details, but a person familiar with the notice said the assistance would involve support to improve awareness at sea.

- Growing tensions -

The assistance needs approval from Congress, which is virtually certain as lawmakers from both parties widely support Taiwan.

Representative Mike McCaul, the Republican chair of the House Foreign Affairs Committee and frequent critic of Biden's foreign policy, praised the step.

"These weapons will not only help Taiwan and protect other democracies in the region, but also strengthen the US deterrence posture and ensure our national security from an increasingly aggressive CCP," he said, referring to the Chinese Communist Party.

China and the United States in recent months have resumed dialogue with hopes of bringing greater stability to the turbulent relationship between the world's largest developed and developing nations.

But Taiwan remains a clear point of friction, with Chinese officials repeatedly issuing warnings and viewing the United States as bent on supporting formal independence by the island.

China has carried out major military exercises three times in little more than a year in response to Taiwanese leaders' interactions with the United States, raising the prospect it is practicing moves for an invasion.

Senior US officials have said they believe Chinese President Xi Jinping is taking steps away from the status quo on Taiwan, although American analysts debate to what extent both China's recent economic concerns and Russia's struggles to subdue Ukraine will dissuade Beijing.

It is the second time in as many months that the Biden administration has broken new ground in supporting Taiwan.

In July, Biden approved $345 million of military aid to Taiwan from leftover US stockpiles, taking a cue from one means of US support to Ukraine as it fights off a Russian invasion.

Israel is the top recipient of Foreign Military Financing, to the tune of more than $3 billion a year.