By Ian Talley

WASHINGTON -- Secretary of State Mike Pompeo on Wednesday said that the unwinding of the U.S. sanctions regime against Iran would be "a dangerous choice," obliquely expressing concerns that the incoming Biden administration would ease the four-year economic pressure campaign.

President Trump's top diplomat, in comments accompanying new Treasury Department sanctions targeting Supreme Leader Ali Khamenei's business empire, defended the campaign as critical to U.S. national security. While Mr. Pompeo didn't mention the next administration directly, his statement was a response to a promise by President-elect Joe Biden to return to the Obama-era nuclear deal with Iran. The terms of that deal, from which the Trump administration withdrew, include rolling back sanctions.

"Reducing that pressure is a dangerous choice, bound to weaken new partnerships for peace in the region and strengthen only the Islamic Republic," Mr. Pompeo said in a statement.

The secretary called the policy "extraordinarily effective" and promised additional sanctions in the last weeks of the Trump administration, a move that some officials and analysts say is part of a broader effort to preserve U.S. diplomatic leverage.

Iranian officials have previously condemned the sanctions and said they wouldn't coerce Tehran into negotiations.

"These latest attempts to continue a failed policy of 'maximum pressure' against Iran and its citizens will fail, just as all other attempts have, " said Alireza Miryousefi, spokesman at Iran's mission to the United Nations. "Imposing new sanctions or designations are merely a sign of desperation of an administration who sees no achievement for its failed policy against Iran."

During his campaign, Mr. Biden called the Trump Iran policy "a bust" and critics say the U.S. effort failed to achieve its primary stated goal of securing a new nuclear and security deal.

The Trump administration's decision to exit from the 2015 nuclear deal was opposed by key European allies who helped negotiate the accord, a decision that fueled a broad-based diplomatic rift with the U.S. The withdrawal's critics say the maximum pressure campaign has crushed Iran's economy without drawing Tehran back to the negotiating table, while at the same time destabilizing the region and encouraging Iran to breach its commitments by enriching more uranium.

"Hostilities may be more likely if U.S. commitments in negotiations are not credible and countries cannot access an off-ramp from sanctions," said Elizabeth Rosenberg, a senior fellow at the Center for New American Security now serving in the Biden transition team, in an August CNAS report. "An adversary may conclude that if there is no negotiating path out of significant economic pressure, they may escalate militarily, a dynamic that already seems to be in play with respect to Iran."

In defense of the administration's policy, Mr. Pompeo pointed to Iran's economic crisis, saying the campaign had denied Iran access to more than $70 billion in oil revenue and would continue to cut potential income by around $50 billion a year. While the easing of sanctions under the nuclear deal allowed Iran to expand its defense budget by 30% between 2016 to 2018, the Trump sanctions forced a 25% cut in defense spending last year, he said.

"These sanctions deprive the regime of funds it would use to carry out its malign activities," Mr. Pompeo added.

Elliot Abrams, the State Department's special envoy for Iran and Venezuela policy, told The Wall Street Journal late last month that Iran hasn't entered into negotiations because it is waiting to see if the U.S. will ease pressure.

"We're confident that if pressure is maintained, the regime will enter into a negotiation next year. It's been waiting to see the outcome of the election," he said in an interview.

Wednesday's sanctions blacklisted a foundation controlled by Mr. Khamenei that U.S. Treasury officials said represents a multibillion-dollar economic empire the leader uses to enrich his office, reward political allies and persecute the regime's enemies. Iran analysts say the Bonyad Mostazafan, while posing as a charitable organization, is run by the Islamic Revolutionary Guard Corps, an elite military organization designated by the U.S. as a terrorist group.

Analysts also say Bonyad Mostazafan has procured goods and technology for the country's weapons-of-mass-destruction programs.The sanctions also hit several of the foundation's top officials and dozens of its subsidiaries operating across Iran's key sectors, including energy, mining and finance.

Bonyad Mostazafan didn't immediately respond to a request for comment, but the foundation's sanctioned president, Parviz Fattah, said in a tweet that the sanctions wouldn't undermine its operations.

Write to Ian Talley at ian.talley@wsj.com

(END) Dow Jones Newswires

11-18-20 1610ET