U.S. National Security Adviser H.R. McMaster on Sunday tried to smooth ruffled feathers in Korea by clarifying that the U.S. will indeed pay the roughly US$1 billion for the Terminal High-Altitude Area Defense battery being stationed here.

"What I told our South Korean counterpart is until any renegotiation, that the deal is in place, we will adhere to our word," McMaster told Fox News.

U.S. President Donald Trump incensed tempers in Seoul last week by saying in an interview that he wants South Korea to pay.

But McMaster tried to make light of the remarks. "The last thing I would ever do is contradict the president of the United States," he said. "And that's not what it was. What the president has asked us to do, is to look across all of our alliances and to have appropriate burden sharing-responsibility sharing. We're looking at that with our great ally South Korea, we’re looking at that with NATO."

A diplomatic source in Washington said, "The mood in Washington is that pulling the THAAD battery out of South Korea at the risk of destroying the South Korea-U.S. alliance is not possible."

Cheong Wa Dae said McMaster's comments appear to confirm the existing agreement, whereby the U.S. pays for the equipment, which mostly serves to protect U.S. personnel and equipment here, while South Korea provides the land.

Defense Ministry spokesman Moon Sang-gyun told reporters, "I don't think it's an issue for renegotiation." And Foreign Minister Yun Byung-se said that he believes the U.S. emphasis is on upholding the agreement.

Meanwhile, U.S. Vice President Mike Pence told NBC News that Trump has been calling on Washington's allies to "play a bigger role," a theme that had been running through Trump's presidential campaign before he had much understanding of the existing cost-sharing agreements.

