Washington (CNN) The U.S. harshly criticized the human rights records of Iran and Cuba Thursday, even as Washington tries to create new understandings with both countries.

The State Department also made clear that even if some sanctions are lifted on Iran as part of a nuclear deal, those related to human rights abuses would stay in place.

The State Department's annual human rights report rapped Iran for "cruel, inhuman, or degrading treatment" of its citizens on the eve of a final round of talks aimed a reaching an agreement to curb Tehran's nuclear program.

The report cited U.N. and human rights groups' findings that the government was responsible for unlawful and arbitrary killings and 721 executions, the second-highest rate in the world. In addition, the report pointed to around 900 political prisoners being held in Iran, including at least 30 journalists.

The report did not specifically mention Washington Post reporter Jason Rezaian, who has been held in Iran for more than 11 months and is on trial for espionage. Rezaian is jailed in Iran's Evin Prison, which was singled out as being "notorious for cruel and prolonged torture for political opponents of the government," including extreme sensory deprivation and isolation.

The report's release was delayed four months beyond the legal requirement. Critics accused the State Department of withholding it to avoid embarrassing Iran before the June 30 deadline for a nuclear deal. The State Department, however, blamed the delay on Secretary of State John Kerry's travel and recent biking injury, which kept him out of the office for several days.

Official said Kerry wanted to release the report as an expression of his commitment to human rights. He leaves Friday for a final round of nuclear talks in Vienna with Iranian officials.

The State Department's annual terrorism report, published last week, also had harsh words for Iran. It found that the country's sponsorship of terrorism worldwide last year remained "undiminished."

The report specifically pointed to Tehran's support for Palestinian terror groups, its Lebanese proxy Hezbollah and several groups in Iraq. It additionally accused Tehran of "prolonging the civil war in Syria, and worsening the human rights and refugee crisis there."

The heavy criticism found in the two reports suggested that neither improved relations with the West as a result of nuclear negotiations nor the leadership of Iran's reformist President Hassan Rouhani had moderated Iran's treatment of its people or its regional foreign policy.

"I can't say that we have seen any meaningful improvement in the human rights situation in Iran" over previous years, said Tom Malinowski, the State Department's top official on human rights.

But he reaffirmed longstanding U.S. policy that the ongoing nuclear talks are "to deal with the nuclear issue. It is not to deal with the human rights issue. It's a separate concern."

"Regardless of the outcome of the Iran talks, we are going to continue to speak up and stand out and stand up for human rights in Iran," Malinowski said. "If any sanctions are lifted as a result of a nuclear deal, the human rights-related sanctions will remain in place."

Unsurprisingly, the report offered bleak assessments of longtime human rights trouble spots like North Korea and Syria. It also had tough words for China, with which the U.S. just wrapped up two days of intensive political and financial talks, and Russia, where it cited a crackdown on political opposition and called President Vladimir Putin's government "increasingly authoritarian," pointing to "a range of new measures to suppress dissent within its borders."

On Cuba, the report found that while the government has largely eased travel restrictions since January, when Washington and Havana announced plans to restore ties, passport requests for certain opposition figures were denied and others were harassed upon returning to Cuba.

"Most human rights abuses were committed by officials at the direction of the government. Impunity for the perpetrators remained widespread," the report said.

In response to questions from reporters, Malinowski noted the U.S. opening to Cuba was "associated very closely" with the release of over 50 political prisoners. But he noted there has not been a let-up in the "day-to-day harassment that civil society activists face in Cuba."

"The situation needs to get far better before any of us can say that we're where we want to be," Malinowski said.

But he argued that the changes in U.S. policy are "better suited to promoting human rights" because of increased engagement.

Last month Malinowski led the first formal human rights dialogue between the U.S. and Cuba since President Barack Obama and Cuban President Raul Castro announced they were seeking to normalize relations.

The report also cited a sharp increase in atrocities by extremist groups and non-state actors such as ISIS and Boko Haram.

But some allies fighting ISIS as part of the U.S.-led coalition were also admonished in the report. Saudi Arabia's government was cited for trying several human rights activists, severely limiting the exercise of religious freedom and continuing to restrict women's opportunities through its guardianship system and driving ban.

Kuwait was criticized for sentencing an activist to five years in prison for "defaming the emir" via Twitter.

Kerry, who entered the State Department briefing room Thursday on crutches, urged leaders who are uncomfortable with the report's findings to use them as a tool to improve their human rights practices.

"That is the advice that we also give to ourselves," Kerry said. "There's nothing sanctimonious, there is zero arrogance."

In a nod to the recent shooting at a black church in Charleston and riots in Baltimore and Ferguson, Missouri, Kerry said the U.S. "couldn't help but have humility when we have seen what we have seen in the last year in terms of racial discord and unrest."