WASHINGTON－The United States said on Wednesday it will terminate sanctions waivers for nations that remain in the Iran nuclear accord, bringing the deal further to the verge of collapse.

US Secretary of State Mike Pompeo said he was responding to Iran's "brinkmanship" of nuclear steps, which have been aimed at pressuring the US to remove sanctions as called for by the 2015 accord.

"These escalatory actions are unacceptable and I cannot justify renewing the waiver," Pompeo said in a statement.

US President Donald Trump bolted from the agreement negotiated under his predecessor Barack Obama, under which Iran had drastically curbed its nuclear activities.

But the Trump administration until now had issued waivers to allow companies, primarily from Russia, that are still present in Iran to carry out the agreement.

The US will notably remove the waivers that allowed the modification of the heavy water reactor in Arak, which prevented it from using plutonium for military purposes, as well as the export of spent and scrap research reactor fuel.

Pompeo said that the US was issuing a final 60-day waiver to allow companies involved in the projects to wrap up their operations.

Washington, however, did not move to stop international support for Bushehr, oil-rich Iran's only nuclear power plant, where Russia has been supplying fuel.

Pompeo said the US was providing a 90-day waiver extension on Bushehr to "ensure safety of operations", but reserved the right to modify it at will.

In justifying the moves, Pompeo also pointed to recent comments by Iranian Supreme Leader Ayatollah Ali Khamenei, who said it was an "Islamic duty" to fight for the "liberation of Palestine" and denounced supporters of Israel.

'Another bad move'

But the other parties of the 2015 nuclear accord still support the deal, saying that it was working by reducing Iran's nuclear activities.

The Trump administration, which has close ties both with Israel and Iran's regional rival Saudi Arabia, called the deal a "disaster", and said the larger issue was reducing Teheran's activities in the region.

Trump's presumptive opponent in the coming presidential election, Joe Biden, supports the deal, arguing along with US allies the United Kingdom, France and Germany that it had worked effectively in constraining Iran until Trump walked out and imposed sanctions.

Analysts said ending the sanctions waivers is counterproductive."Another bad move. Trump and Pompeo are trying to goad Iran into abandoning all nuclear constraints," tweeted Mark Fitzpatrick, a nuclear issue expert and former US State Department official.

Iran's economy has faced intense pressure over the sanctions, while Trump has also used military force, killing a senior Iranian general in a January drone strike.

On Thursday, Iranian lawmakers elected Mohammad Baqer Qalibaf, 58, former Teheran mayor, as the speaker of the parliament for one year, state television reported.

Qalibaf served in Iran's Revolutionary Guard during the country's 1980s war with Iraq. After the conflict, he once served as the head of the Guard's air force.

Agencies - Xinhua