STANFORD, Calif., Feb. 9 (UPI) -- The 31st anniversary of the Islamic Revolution on Thursday could be a bellwether moment for the clerical regime in Tehran, analysts said.

Supporters of the opposition Green Movement are said to be planning protests to coincide with the anniversary of the Islamic Revolution on Thursday.

Reports in January suggested the opposition may infiltrate pro-regime celebrations and wave their signature green banners before state-run news agencies covering the event.

Tehran said it was processing applications for hundreds of foreign journalists to cover the rallies Thursday following months of restrictions.

Abbas Milani, who directs the Iranian studies program at Stanford University, said the Thursday rallies could mark a sea change depending on the level of support from both sides, The Wall Street Journal reports.

"For both sides, this is almost a make-or-break day," he said.

Contested June presidential elections gave rise to a seemingly durable anti-government movement in Iran. Protests on the Shiite holy day of Ashura in December turned deadly as protesters clashed with riot police.

Milani said that, as was the case when revolutionaries overwhelmed national security forces in 1979, the Thursday events could prove noteworthy.

"If the opposition doesn't have a good showing, it will be a big setback," he told the Journal. "If the regime, despite throwing everything at (preventing demonstrations), doesn't stop the protests, they'll have to rethink their strategy."

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