The case of an Iranian pastor facing a possible death sentence has reportedly been referred to Iran's supreme leader, a move some say shows the Islamic republic is feeling pressure in the face of growing international support.

Attorney Mohammad Ali Dadkhah told AFP on Monday that an Iranian court has decided to seek the opinion of Ayatollah Ali Khamenei -- the Islamic republic's spiritual leader and highest authority -- in the case of Youcef Nadarkhani, a 32-year-old pastor who was arrested in October 2009 and later sentenced to death for converting to Christianity.

Dadkhah and religious rights organizations say Nadarkhani is facing possible execution for apostasy and for refusing to renounce his religion, contradicting reports by Iran state media that have indicated Nadarkhani was found guilty of rape, extortion and security-related crimes. Messages seeking comment from Dadkhah were not immediately returned early Monday.

Jordan Sekulow, executive director of the American Center for Law and Justice, a Washington-based organization that is monitoring Nadarkhani's case, told FoxNews.com that the move was unusual and is part of the "secretive process" within the Iranian judicial system.

"Based on these reports, Pastor Youcef is alive and we have reached the highest level of Iranian government," Sekulow said on Monday. "I don't believe this would've ever reached the level of Khamenei without the media attention and outpouring of support we've seen."

Sekulow said the move to involve Khamenei in a case before a regional court is uncommon and indicates that "Iran is feeling the pressure" of the growing international community in support of Nadarkhani.

As of Friday, at least 39 members of Congress had signed a letter calling on Secretary of State Hillary Clinton to put pressure on Iranian authorities to release Nadarkhani, who, according to reports last week from Iranian state-funded Press TV, is now considered a security threat and previously operated a brothel. Judiciary Chief Mohammad-Javad Heshmati of Iran's Gilan Province told the station on Wednesday that no verdict had been reached and that an execution order had not yet been issued.

Documents obtained by the American Center for Law and Justice, however, indicate that apostasy is the only charge against Nadarkhani.

"There was an indication that this would go to one of [Iran's] top leaders," Sekulow said of Nadarkhani's case. "It looks like everything we believed would happen has now happened. This is the time where the international pressure, the media attention, has to increase tenfold."

Sekulow also asked Clinton to call for Nadarkhani's "unconditional release" and said more than 125,000 people have signed a petition in support of the father of two. Calls seeking comment from the U.S. State Department were not immediately returned on Monday.

The White House condemned the conviction and possible death sentence for Nadarkhani late last month, saying the execution would further demonstrate Iranian authorities' "utter disregard" for religious freedom.

"Pastor Nadarkhani has done nothing more than maintain his devout faith, which is a universal right for all people," the statement released by the White House on Sept. 29 read. "That the Iranian authorities would try to force him to renounce that faith violates the religious values they claim to defend, crosses all bounds of decency, and breaches Iran's own international obligations. A decision to impose the death penalty would further demonstrate the Iranian authorities' utter disregard for religious freedom, and highlight Iran's continuing violation of the universal rights of its citizens. We call upon the Iranian authorities to release Pastor Nadarkhani, and demonstrate a commitment to basic, universal human rights, including freedom of religion."

Nadarkhani is the latest Christian cleric to be imprisoned in Iran for his religious beliefs. According to Elam Ministries, a United Kingdom-based organization that serves Christian churches in Iran, there was a significant increase in the number of Christians arrested solely for practicing their faith between June 2010 and January 2011. A total of 202 arrests occurred during that six-month period, including 33 people who remained in prison as of January, Elam reported.

Nadarkhani, a pastor in the 400-member Church of Iran, has been held in that country's Gilan Province since October 2009, after he protested to local education authorities that his son was forced to read from the Koran at school. His wife, Fatemeh Pasandideh, was also arrested in June 2010 in an apparent attempt to pressure him to renounce his faith. She was released in October 2010, according to Amnesty International.