A Senate committee on Wednesday took the first step toward the United States by providing billions of dollars in military aid directly to Taiwan and making ties more official by boosting support following rising tensions with Beijing.

The United States has sold arms to Taiwan for decades, but the new legislation will go further by providing $4.5 billion in US security aid over four years, a move sure to infuriate Beijing. It also envisages sanctions against China if it attempts to seize the island by force.

With bipartisan support, the Senate Foreign Relations Committee passed the Taiwan Policy Act, touted as the biggest improvement in relations since the United States shifted recognition from Taipei to Beijing in 1979.

Lawmakers pushed the law ahead amid heightened concerns about Taiwan following Russia’s invasion of Ukraine and after a visit by House Speaker Nancy Pelosi to Taipei that prompted China to hold major military exercises seen as a dry run for an invasion became.

Senator Bob Menendez, a member of Biden’s Democratic Party who chairs the committee, said the United States “needs not to seek war or heightened tensions with Beijing” but “to be clear-eyed.”

“We are cautiously and strategically reducing the existential threats Taiwan faces by increasing the cost of taking the island by force so that the risk becomes too high and unattainable,” Menendez said.

Senator Jim Risch, the top Republican on the committee, said it was “imperative that we take action now to strengthen Taiwan’s self-defense before it’s too late.”

The bill still has to be approved by the full Senate and House of Representatives. The White House hasn’t said whether President Joe Biden will sign the bill into law, although the strong support it has could mean Congress could override any possible veto.

Under the law, the United States will still not recognize Taiwan.

China regards the island – where the defeated mainland nationalists fled in 1949 – as a province awaiting reunification and staunchly defies any international legitimacy for Taipei, which has transformed itself into a vibrant democracy and major economic power.

But the new law would drop many of the previous evasions and code words so as not to anger China with the implicit recognition.

The de facto embassy – now officially the Taipei Economic and Cultural Representative Office – would be renamed the Taiwan Representative Office, and the US government would be directed to interact with Taiwan as it would any other government.

The top US envoy in Taipei, now called the director of the American Institute in Taiwan, would be renamed the bureau’s “representative” and would have to be confirmed by the Senate, as would a US ambassador.

The law would also designate Taiwan as a “key non-NATO ally,” a status for the closest US military partners outside the transatlantic alliance. And considering the changing dynamic since the landmark Taiwan Relations Act of 1979, the bill says the United States will provide weapons that “help deter acts of aggression” by China, not just “defensive” weapons.

In addition to the $4.5 billion in funding for Taiwan, the law would authorize $2 billion in loan guarantees for Taiwan to purchase US weapons.

Biden appeared to end decades of US ambiguity earlier this year, saying the United States would directly aid Taiwan if it was attacked.

His staff refuted his remarks, and the White House later quietly advised Pelosi not to go ahead with her visit, fearing it would provoke President Xi Jinping ahead of a key Communist Party meeting.

White House press secretary Karine Jean-Pierre said only that the Biden administration is in contact with lawmakers about the legislation.

“We appreciate the strong bipartisan support for Taiwan and want to work with Congress to strengthen it,” she said.