U.S. President Donald Trump's administration does not have a "bloody nose" strategy for a limited military strike on North Korea, a senior State Department official said Thursday.

"That is my understanding," Susan Thornton, Trump's nominee for assistant secretary of state for East Asian and Pacific affairs, said during her confirmation hearing at the Senate Foreign Relations Committee.

She was responding to a question by Sen. Jeanne Shaheen of New Hampshire, who said she and other senators had been told no such strategy exists in a White House briefing Wednesday.

The strategy, which was said to have been under consideration within the administration, refers to a strike on a military target in North Korea intended to demonstrate U.S. resolve without triggering a full-scale war.

The administration has run a policy of applying "maximum pressure" on North Korea through sanctions while keeping military options on the table in dealing with Pyongyang's pursuit of nuclear weapons and ballistic missiles.

"We will not accept a nuclear North Korea," Thornton said. "Our preference is to achieve denuclearization of the Korean Peninsula through a diplomatic settlement, but we will reach this goal one way or another."

Thornton has been serving as acting assistant secretary of state for East Asian and Pacific affairs since the departure of Daniel Russel, who served under the administration of Trump's predecessor Barack Obama, in March last year.

Aside from the rising nuclear threat posed by North Korea, Thornton cited the rise of an "authoritarian" China, the spread of terrorism and trade imbalances as among security and economic challenges in the Asia-Pacific region.

Thornton advocated a rules-based regional order, saying the United States will not tolerate Beijing's attempts to displace Washington in Asia and to coerce countries in the region.

It is "disappointing" to see China backsliding on economic reforms and political rights, she said.

Referring to China's militarization of outposts in disputed areas of the South China Sea, the official suggested the United States continue freedom of navigation operations and work with like-minded countries to push back on Beijing's unilateral action.

China has overlapping territorial claims with Brunei, Malaysia, the Philippines, Vietnam and Taiwan in the South China Sea, a strategic waterway through which over one-third of global trade passes.

Thornton pledged to support a regional architecture centering on the 10-member Association of Southeast Asian Nations, a framework she said underpins East Asian peace and security.

Echoing Trump's "America First" trade policy, Thornton called for "fair and reciprocal market access" to China, Japan, South Korea and other economies running trade surplus with the United States.

"The export-led model that underpinned East Asia's stunning growth is no longer viable," she said.