Top US diplomat John Kerry said Thursday he would mull ways to deepen US engagement in the Arctic amid pleas from lawmakers to name America's first ambassador to the resource-rich region.

The secretary of state agreed the United States could get left behind in the race to exploit a potential wealth of undersea riches, with China and Russia already looking for ways to move into the territory.

As Arctic waters melt in a trend blamed on global warming, minerals vital in global communications equipment as well as oil and gas once hidden under layers of permafrost are now becoming more accessible.

The seaway has also become more navigable as a shipping route. In August, the first Chinese ship traveled from the Pacific Ocean to the Atlantic via the Arctic along the Russian coast, cutting the route to Europe by about 40 percent.

Kerry said it was vital for the United States to sign the UN Law of the Sea in order to protect American interests in region.

And he plans to attend the next meeting of the Arctic Council -- made up of Canada, Denmark, Finland, Iceland, Norway, Russia, Sweden and the United States -- in Sweden on May 15.

"I think it's beyond critical to us," Kerry told the Senate Appropriations Committee, as he defended the State Department's 2014 budget request.

"The reason China and those other countries are knocking on the door is that they all want get observer status in the council, because the only countries in the council are the countries that border round the Arctic."

The United States is the only industrialized power that has yet to ratify the 30-year-old Law of the Sea, and Kerry urged his former Senate colleagues to take another look.

"Right now, the Chinese and the Russians are laying the map, staking the claim, getting a head start on this sort of reservation on the resources of the future. We're sitting around," he said.

Kerry also urged careful consideration of all the environmental issues connected with seeking to exploit the wealth of the pristine area.

Asked whether he would consider appointing the first American ambassador to the Arctic, Kerry said he was taking notes for himself.

And he offered to give senators a classified briefing to explain why the Arctic was of vital national strategic interest to the United States.