WASHINGTON--The United States will not block China from growing its economy, but wants it to adhere to international rules, Secretary of State Antony Blinken said on Thursday in a long-awaited speech on U.S. strategy to address China's rise as a great power.

Washington will not try to change China's political system, but will defend international law and institutions that maintain peace and security and make it possible for countries to coexist, he said.

"We are not looking for conflict or a new Cold War. To the contrary, we're determined to avoid both," Blinken said in the 45-minute speech at George Washington University, which covered most contentious bilateral issues.

U.S.-China relations sank to their lowest level in decades under former President Donald Trump and have soured further under President Joe Biden, a Democrat who has kept up his Republican predecessor's sweeping tariffs on Chinese goods while pursuing closer ties with allies to push back against Beijing.

Seventeen months into his administration Biden had faced criticism from Republicans and some foreign policy watchers for not announcing a formal strategy on China, the world's second-largest economy and Washington's main strategic rival.

Foreign crises, including the messy U.S. withdrawal from Afghanistan last year and Russia's war in Ukraine, have created distractions for Biden, who has vowed not to let China surpass the United States as global leader on his watch.

But his administration has sought to capitalize on fresh solidarity with allies spurred by the Ukraine crisis and the "no-limits" partnership China announced with Moscow just weeks before Russia's Feb. 24 invasion of its neighbor.

‘MOST SERIOUS LONG-TERM CHALLENGE’

Blinken said China posed "the most serious long-term challenge to the international order."

He laid out the contours of a strategy to invest in U.S. competitiveness and align with allies and partners to compete with China, calling that competition "ours to lose."

He said the Biden administration stood ready to increase direct communication with Beijing across a full range of issues, and would "respond positively" if Chinese officials take action to address concerns.

"But we cannot rely on Beijing to change its trajectory. So we will shape the strategic environment around Beijing to advance our vision for an open and inclusive international system," he said.

In response, China's Washington embassy said the United States and China shared "extensive common interests and profound cooperation potential" and "competition ... should not be used to define the overall picture of the China-U.S. relations."

"China and the U.S. both stand to gain from cooperation and lose from confrontation," embassy spokesperson Liu Pengyu said.

He noted a virtual summit between Biden and Chinese President Xi Jinping last November and said the relationship was "at a critical crossroads."

"We hope the U.S. side will work with China to earnestly implement the common understanding reached by the two leaders to enhance communication, manage differences and focus on cooperation," he said.

‘REPRESSIVE' AND 'AGGRESSIVE’

While Blinken credited the hard work of the Chinese people for their country's historic economic transformation in the last four decades, he took direct aim at Xi Jinping, saying:

"Under President Xi, the ruling Chinese Communist Party has become more repressive at home and more aggressive abroad."

Blinken's speech coincided with the start of a sweeping tour by China's foreign minister of Pacific island countries, an increasingly tense front in competition for influence between Beijing and Washington.

The speech was postponed earlier in May after Blinken tested positive for COVID-19 and follows a month of intensive U.S. diplomacy focused on the Indo-Pacific, including Biden's first trip as president to the region.

Blinken reiterated U.S. commitment to the one-China policy over Chinese-claimed democratic Taiwan, even though Biden earlier this week said the United States would get involved militarily should China attack Taiwan.

Washington has had a long-standing policy of strategic ambiguity on whether it would defend Taiwan militarily and Biden and aides later said his remarks did not reflect a policy shift.

Under the one-China policy, Washington officially recognizes Beijing diplomatically, although it is bound by law to provide Taiwan with the means to defend itself. Blinken said this was unchanged and Washington did not support Taiwan's independence.

"What has changed is Beijing's growing coercion, like trying to cut off Taiwan's relations with countries around the world, and blocking it from participating in international organizations," he said, calling the Chinese military's nearly daily activity near the island "deeply destabilizing."