In a UN Security Council vote on Friday on the US effort to extend the world body's arms embargo on Iran, Russia and China voted against, while 11 members abstained including France, Germany and Britain. The United States and the Dominican Republic were the only votes in favor.
"I don't remember the United States preparing a resolution for months to strike a blow at the Islamic Republic of Iran, and it garners only one vote," Iranian President Hassan Rouhani said in a televised speech. "But the great success was that the United States was defeated in this conspiracy with humiliation."
The UN arms embargo on Iran is due to expire under 2015 nuclear deal between Iran and world powers, which provided for many international sanctions against Iran being lifted in exchange for curbs on Iran's nuclear program. President Donald Trump withdrew the United States from the deal in 2018.
"It's a serious mistake, we regret that," Pompeo said on Saturday of the Security Council vote in a news conference during a visit to Poland.
The United States could now follow through on a threat to trigger a return of all UN sanctions on Iran using a provision in the nuclear deal, known as snapback. Diplomats have said the United States could do this as early as next week, but that it would face a tough, messy battle.
Israeli Foreign Minister Gabi Ashkenazi said the Security Council's decision not to extend the arms embargo on Iran will lead to further Middle East instability.
"The extremist regime in Iran doesn't just finance terrorism: it takes an active part in terrorism through its branches around the world and uses it as a political tool. This behavior represents a danger to regional and international stability," Ashkenazi said in a statement on Saturday.
The Security Council vote followed a proposal made by Russian President Vladimir Putin for a summit of world leaders to avoid "confrontation" over the American threat to trigger a return of all UN sanctions on Tehran.