Secretary of State Mike Pompeo says North Korean leader Kim Jong Un will ultimately determine the timeline for denuclearization of his country.

Speaking to Channel NewsAsia in Singapore on Friday, Pompeo said the “world should be less nervous” than before President Trump’s June summit with Kim in Singapore because “we were in a very different place with frequent missile launches and nuclear testing taking place.”

“None of that has been taking place since June 12. We’re happy about that,” he said, while visiting the country for an Association of Southeast Asian Nations meeting.

The Trump administration has not shared its own timeline for North Korea’s denuclearization and the agreement signed by Trump and Kim in Singapore on June 12 gave no timeline for it, either. Still Pompeo remains optimistic in light of a recent Washington Post report that said intelligence officials are concerned North Korea is building new missiles. However, Pompeo said the U.S. will continue to keep economic sanctions on North Korea.

“The ultimate timeline for denuclearization will be set by Chairman Kim,” he said in the exclusive interview with Channel NewsAsia. “We are confident that [North Korean leader Kim Jong Un] remains committed to denuclearization. The world is counting on it.”

The White House confirmed Thursday that Trump and Kim have continued to communicate since their meeting. Trump thanked Kim early Thursday for his “nice letter” accompanying the likely remains of U.S. soldiers who died in the Korean War.