Support for transforming the "Quadrilatertal Security Dialogue," or Quad, among the United States, India, Australia and Japan into a formal Asian military alliance has grown in the new Biden administration as it sets Asia-Pacific policy, according to a top U.S, diplomat.

National security adviser Jake Sullivan said the Biden administration "really wants to carry forward" the work started by former President Donald Trump in strengthening the capabilities of Quad beyond an informal grouping of countries determined to stand-up to China.

The Quad has long been referred to as the "Asian NATO" because of the immense potential military power, especially the naval forces of its four partners.

Speaking at the online United States Institute for Peace forum, Sullivan said bolstering Quad into a military organization is a goal of the Biden administration.

He affirmed "the number one geopolitical challenge to the United States is China." He said China has become "increasingly nationalistic" with its crackdown on pro-democracy citizens in Hong Kong and Muslim Uighurs in China's Xinjang Autonomous Region.

Sullivan also underscored China's "unrelenting global ambitions" that extend from the South China Sea to the East China Sea and up to the Arctic with its vast untapped mineral wealth China desperately needs to grow its economy.

But Sullivan said the U.S. needs "to be in lockstep with allies and partners" that share a common concern about China's territorial ambitions. He said the democracies comprising the future Quad means "we're going to stand up for principle."

Sullivan also said the U.S. "needs to keep its technological edge" in artificial intelligence (AI) and quantum computing to show it remains a superpower and a model for economic development.

An initiative of former Japanese Prime Minister Abe Shinzo, the Quad seeks to establish an "Asian arc of democracy." This arc will include countries in Central Asia, Mongolia, South Korea, and Southeast Asia and "virtually all the countries on China's periphery -- except for China itself," according to Quad.

Over the weekend, the United Kingdom indicated its readiness to join Quad.