WASHINGTON — President Donald Trump on Friday kept alive the Iran nuclear deal he detests by waiving sanctions for the third time, but he said he will not repeat the reprieve unless the agreement is amended to permanently block a potential pathway to build nuclear weapons.

In conjunction with the waivers, the Treasury Department placed sanctions on 14 people and entities for alleged offenses unrelated to Iran’s nuclear industry. They concern human rights abuses and censorship in Iran and its arming of groups throughout the region.

Trump’s decision avoided placing the United States immediately in violation of the commitments it made in the 2015 deal. But he signaled his willingness to withdraw from the deal in a few months unless changes are made.

“The president makes clear this is the last such waiver he will issue,” said a senior administration official, speaking on the condition of anonymity under rules for briefing reporters. “He intends to work with our European partners for a follow-on agreement.”

Among the changes Trump demands is timely inspections of all sites requested by the International Atomic Energy Agency, and an end to expiration dates sometimes called “sunset provisions” so the United States can snap back sanctions forever if Iran is ever found to be cheating.

Trump also is demanding a breakout time of more than one year. The 2015 deal extended the breakout time - how long it takes to amass enough fissile material to construct one nuclear bomb - from two months to one year.

Some of the new sanctions announced by the Treasury Department are a response to crackdowns on anti-government protests in Iran in which access to social media was blocked.

The designations include Iran’s Supreme Council of Cyberspace and its subsidiary, the National Cyberspace Center, which police the internet, restricting access to various websites that challenge the regime as well as the proxies and virtual private networks many Iranians rely on to get around the controls.

The sanctions with the most political repercussions are against Sadegh Amoli Larijani, the administrative head of Iran’s judiciary.

Larijani, a hard-line cleric appointed by Iran’s supreme leader, Ayatollah Ali Khamenei, is a highly influential figure and member of Iran’s most powerful political family. His older brother, Ali Larijani, is the speaker of Iran’s parliament.

Iran’s judicial system is notoriously repressive, and the country remains one of the world’s leading executioners. According to the European Union, which placed its own sanctions on the judiciary chief in 2012, Larijani has “personally signed off on numerous death penalty sentences.”

“Arbitrary arrests of political prisoners, human rights defenders and minorities have increased markedly” under his tenure, the E.U. said.

In his written works and other statements, Larijani often has spoken of his opposition to “cultural invasion” from the West.

“Naming and shaming Sadegh Larijani is one small way the U.S. can bring its human rights policy and coercive economic strategy against Iran into greater alignment,” said Behnam Ben Taleblu, Iran expert at the Foundation for Defense of Democracies in Washington.

Other sanctions target several companies accused of conducting prohibited transactions with Iranian entities. Malaysia-based Green Wave Telecommunications was barred for providing U.S. technology to Iranian companies. The Treasury Department also listed several Chinese individuals and companies for breaking similar rules to provide materials to Iran that could be used in navigation and weapons systems.

This week, officials from Iran’s Atomic Energy Organization threatened to boost uranium enrichment and cease cooperation with the International Atomic Energy Agency if Trump violated the deal. The IAEA, a United Nations watchdog, monitors Iran’s compliance with the agreement.

Iran’s nuclear chief, Ali Akbar Salehi, reportedly spoke with IAEA head Yukiya Amano by phone Monday, Iran’s state-run Islamic Republic News Agency (IRNA) reported.

According to IRNA, Salehi told Amano that if the United States fails to honor its commitments under the deal, “Iran will adopt measures that can affect the current trend of Iran’s cooperation with the agency.”

No other country requires its leaders to periodically justify the deal the way the U.S. president must, but Congress enacted a law with the requirement out of deep and abiding mistrust of Iran’s intentions.

“The president has been very clear, okay, that many aspects of the Iran deal need to be changed; that there are many activities outside of the Iran deal, whether it be ballistic missiles, whether it be other issues, that we will continue to sanction that are outside the JCPOA,” Treasury Secretary Steven Mnuchin said Thursday, using an abbreviation for the deal’s formal name, the Joint Comprehensive Plan of Action.

“Human rights violations — we couldn’t be more focused,” he said. “We have as many sanctions on Iran today as we have on any other country in the process. And we’ll continue to look at things.”

White House press secretary Sarah Huckabee Sanders said that Trump “still strongly believes this was one of the worst deals of all time.”

“One of the single greatest flaws is that its restrictions leave Iran free in the future to openly develop their nuclear program and rapidly achieve a nuclear weapons breakout capability. Obviously we see big problems with that,” Sanders said. “The administration is continuing to work with Congress and with our allies to address those flaws.”