North Korea Is Still Producing ‘Fissile Material’ Despite a Pledge to Denuclearize, Mike Pompeo Says

North Korea has continued producing fuel for nuclear weapons despite leader Kim Jong Un’s support for denuclearization at a summit with President Donald Trump last month, Secretary of State Mike Pompeo told a Senate hearing Wednesday.

Speaking before the Senate Foreign Relations Committee, Pompeo said that North Korea “[continues] to produce fissile material” in response to a question by Massachusetts Senator Ed Markey, Reuters reports. Pompeo declined to address further questions about North Korea’s weapons program, including whether the country is still pursuing submarine-launched ballistic missiles, in the public setting.

Pompeo appeared before the committee for a wide-ranging hearing that also addressed the Trump administration’s response to Russian election interference, President Trump’s meeting with Putin in Helsinki, and tensions with Iran.

The Secretary of State defended the administration’s progress since the landmark June 12 Singapore summit, saying the U.S. was pursuing “patient diplomacy” to persuade North Korea to abandon its weapons program, “but we will not let this drag out to no end,” he said.

“Progress is happening. We need Chairman Kim Jong Un to follow through on his commitments made in Singapore,” Pompeo said according to Agence-France Presse.

But some diplomats charge little gains have been made since the summit. North Korea lashed out at the administration’s “gangster-like” demands following a visit by Pompeo to Pyongyang earlier this month.

Though Kim signed an accord at the Singapore summit “to work toward complete denuclearization of the Korean Peninsula,” experts have warned that the historic adversaries may differ on what “denuclearization” means in practice.

Read more: Why North Korean Denuclearization Is Still a Long Shot

Still, satellite images revealed that North Korea recently began dismantling a key satellite and missile facility in a possible “first step” toward honoring agreements made in Singapore, North Korea monitoring group 38 North said earlier this week.