North Korean leader Kim Jong-un should follow in Iran's footsteps and negotiate away its nuclear program, a senior American diplomat said, stressing the deal shows the U.S. honors its promises.

"We have extended our hand, but Pyongyang will not unclench its fist. Mr. Kim need look no further than the Iran deal. We keep our word," U.S. Assistant Secretary of State Daniel Russel said during a trip to Singapore last Friday, according to a speech text provided by the newsletter Nelson Report.

"A better path is open to North Korea if it will honor its commitments, negotiate denuclearization, and comply with international law," Russel said.

In July, Iran and six world powers, including the U.S., reached a landmark deal that calls for curbs on Tehran's nuclear program in exchange for removal of sanctions that had crippled the Middle Eastern nation's economy.

The U.S. lifted nuclear sanctions in Iran earlier this month as Tehran fulfilled its commitments.

Six-party talks on North Korea's nuclear program have been stalled since late 2008. The U.S. and South Korea have demanded the North take concrete steps demonstrating its denuclearization commitments in order to reopen the negotiations.

Russel said the U.S. and its partners have a strategy of deterrence, pressure, and diplomacy to deal with the North.

"To maintain deterrence, we are modernizing our security alliances with South Korea and Japan. To keep up pressure, we are enacting stronger sanctions, including at the U.N.," Russel said.

"We are mobilizing the international community to obstruct North Korea's proliferation activities and to confront its human rights abuses -- Pyongyang's protests show this is hitting home."

Those measures are not to punish the North, but to show Pyongyang's leadership that "the world will never accept them as a nuclear armed state or provide economic assistance absent denuclearization," Russel said.

Pyongyang should accept it has "no viable alternative to a negotiated end to their nuclear and missile programs," he said. (Yonhap)