Youcef Nadarkhani, an Iranian pastor who in 2010 was found guilty of apostasy and sentenced to death for refusing to recant Christianity, may have received a final execution order, according to the American Center for Law and Justice and Fox News.

Neither Human Rights Watch nor Amnesty International could verify the information for The Huffington Post, but the White House on Thursday afternoon issued a statement condemning the reports and calling on Iran to release Pastor Nadarkhani.

"This action is yet another shocking breach of Iran’s international obligations, its own constitution, and stated religious values," the White House statement read. "The United States stands in solidarity with Pastor Nadarkhani, his family, and all those who seek to practice their religion without fear of persecution -- a fundamental and universal human right."

While unable to verify the reports, Faraz Sanei, the Iran researcher at Human Rights Watch, spoke with The Huffington Post in a telephone interview about the uncertain circumstances surrounding Nadarkhani.

"A death sentence that has been sent for implementation by the judiciary would suggest the person is at imminent risk of execution," Sanei said. "If it has been sent to the implementation department, that is very troubling."

Sanei added that if the implementation has indeed been sent, Nadarkhani is "one step closer" to being executed.

Islam is the official religion in Iran, and according to the CIA, 98 percent of the country's population is Muslim.

According to Amnesty International, Pastor Naderkhani, 34, became a Christian when he was a teenager and has said he never practiced Islam despite being born to Muslim parents. He has been a pastor for at least 10 years, according to the Christian Post.

In September, the Iranian Supreme Court upheld Naderkhani's 2010 conviction of apostasy after he reportedly refused to recant his Christian faith.