|US Secretary of State Mike Pompeo testifies before a Senate committee hearing on Wednesday.|
Pompeo's remark appeared to signal some flexibility in Washington's position in negotiations with Pyongyang over its nuclear weapons program.
A second summit between US President Donald Trump and North Korean leader Kim Jong-un in February ended without a deal in part over the issue of sanctions relief for the regime.
Pompeo was speaking to the Senate Foreign Relations Committee and asked by Sen. Cory Gardner (R-CO) whether he agrees that no sanctions should be lifted until North Korea demonstrates a commitment to complete and verifiable denuclearization.
"I want to leave a little space there," he answered. "From time to time, there are particular provisions that if we were making substantial progress that one might think that was the right thing to do to achieve. Sometimes it's visas. I want to leave a little room."
The Trump administration has insisted on keeping sanctions on North Korea until denuclearization is achieved. South Korean President Moon Jae-in, an advocate of engagement with Pyongyang, is due to meet with Trump at the White House on Thursday to try to break the impasse.
Pompeo added that Gardner's point was well taken.
"The enforcement regime, the core UN Security Council resolutions, need to remain in place until the verification of denuclearization has been completed," he said.
After the Hanoi summit collapsed, North Korean officials claimed that they had asked for the removal of sanctions under five UNSC resolutions in exchange for the complete dismantlement of their main nuclear facility in Yongbyon.
US officials retorted that those were effectively all the sanctions and that the North Koreans were "parsing words."
Experts have said that if Moon can secure a commitment from Trump to ease sanctions on the regime, this will empower the South Korean leader to persuade his North Korean counterpart to make larger concessions on denuclearization.
Pompeo acknowledged that while more can be done to tighten sanctions enforcement against North Korea, no previous administration had achieved as much success in pressuring the regime.
"We have the largest coalition and the strongest sanctions and sanctions enforcement in history on North Korea. It's what has created this opportunity for diplomacy," he said. "We've not moved as far, but I think we always knew this would be a long discussion."
Sen. Ed Markey (D-MA) called for still stronger sanctions on North Korea, saying Trump's recent withdrawal of additional sanctions sent the wrong message to both North Korea and the rest of the international community.
Moreover, he said, a UN panel recently reported massive increases in ship-to-ship transfers of oil to North Korea in defiance of sanctions.
"You may think the enforcement regime is ineffective, but you should move to the outskirts of Pyongyang because those folks think it's very effective," Pompeo said.
"I don't know about massive, but let me assure you, there's less coal, less fuel, less resource there today than there was when President Obama was in office," he added. (Yonhap)