But nearly six weeks after President Trump's summit with Kim Jong Un, it's unclear where those talks stand and how successful the U.S. diplomatic push has been or even could be.
Pompeo traveled to New York Friday to join Haley for a meeting with the U.N. Security Council representatives, including Chinese and Russian representatives, for what Haley called "frank talk."
"We put pressure today on China and Russia to abide and be good helpers through this situation and to help us continue with denuclearization," she said after the meetings.
Pompeo and Haley also met with the South Korean Foreign Minister Kang Kyung-wha and the U.N. Secretary-General Antonio Guterres, both of whom have supported the Trump administration's negotiations with North Korea.
While Pompeo declared that the U.N. Security Council was "united on the need for final, fully verified denuclearization of North Korea, as agreed to by Chairman Kim," he said, "Strict enforcement of sanctions is critical to achieving this goal."
But in what seemed like a warning if talks fell apart, he added, "When sanctions are not enforced, the prospects for the successful denuclearization of North Korea are diminished."
The U.S. and North Korea have met twice this week, but to discuss the return of remains of Americans who were prisoners of war or missing in action during the Korean War. After Pompeo's third trip to Pyongyang, North Korea released a scathing statement, saying the U.S. made "gangster-like" demands and calling the meetings "regrettable" and even "cancerous."
The administration has pushed back on those characterizations and said the talks between the two sides continue to move forward, with working groups established.
"The conversations continue ... We're working on it. We have teams in place that are working very hard on this issue every day," State Department spokesperson Heather Nauert said Wednesday.
But North Korea has taken no demonstrable steps towards denuclearization, and now, according to Pompeo and Haley, it is violating those sanctions with Chinese and Russian help by illegally smuggling petroleum products into the country at levels higher than allowed by U.N. sanctions.
Pompeo said in the first five months of this year, there were at least 89 ship-to-ship transfers of oil -- an evasive practice where sanctioned products are exchanged in international waters by ships that often hide or obscure their identity. Haley added that the U.S. has "photographs of proof" of those transfers and that they continue to happen.
At the U.N. Thursday, the U.S. proposed a halt to all additional oil shipments because of these violations, but China and Russia blocked it, saying they needed more information.
"We don't need any more information," Haley said Friday. "The problem that we are encountering is that some of our friends have decided that they want to go around the rules."
Despite the sanctions violations, Pompeo said President Trump and he both remain "upbeat about the prospects of denuclearization."
"The path ahead is not easy, it will take time. But our hopes for a safer world for all of us and a brighter future for North Korea remains our objective, and that hope endures," he said.
If the path to get there is "not easy," it is "pretty straightforward," Pompeo said. The U.S. needs to "see Chairman Kim do what he promised the world he would do" and completely denuclearize, "the scope and scale of that is agreed to. The North Koreans understand what that means."