China considers recovering control over Taiwan its "number-one priority," Admiral John Aquilino, nominated to become commander of the US Indo-Pacific Command, told the Senate Armed Services Committee.

"The rejuvenation of the Chinese Communist Party is at stake" with the Taiwan issue, he said.

Aquilino disagreed with outgoing Indo-Pacom commander Admiral Philip Davidson's recent comments that China could attempt to attack and take over Taiwan as soon as six years from now.

"My opinion is that this problem is much closer to us than most think and we have to take this on," he told the panel, which was reviewing his nomination.

Aquilino said the threat was such that the United States needs to implement a proposed $27 billion plan to boost US defenses in the region "in the near term and with urgency."

"The Chinese Communist Party has generated some capabilities in the region that are designed to keep us out," he said.

"The most dangerous concern is that of a military force against Taiwan."

Aquilino though declined comment on the suggestion by Republican Senator Tom Cotton, a hawk regarding the Chinese threat, that Beijing could opt to attack Taiwan as early as next year.

Cotton noted that Russia invaded and occupied Crimea in 2014 just days after it hosted the Winter Olympics.

China, he noted, will host the Winter Olympics in February 2022.

Democratic and self-ruled Taiwan split from China at the end of a civil war in 1949, and is a longtime US ally.

But Beijing has always maintained its claim of sovereignty over the island.

Aquilino, currently the head of the US Pacific fleet, stressed that there were two major concerns of letting China seize Taiwan.

First is the potential threat to global trade, much of which passes the island.

Second, he said, is the damage that would have on US credibility with its Asian allies like Japan, South Korea and the Philippines.

"The status of the United States as a partner with our allies and partners also is at stake should we have a conflict in Taiwan," he said.