Updated

Iranian opposition leader Mir Hossein Mousavi is expected to attend at a rally Wednesday amid an intensifying government crackdown on protesters following the country's disputed presidential election.

Mousavi's attendance is noted on his Facebook page, and there is speculation that former President Mohammad Khatami also will attend the rally, scheduled for 4 p.m. (7:30 a.m. EDT) in Tehran's Baharestan Square, outside of the Iranian parliament.

Also on Mousavi's Facebook page, online supporters have posted that peaceful protests will be held at the same time in over 15 countries and 10 American cities.

Click here to view Mousavi's Facebook page.

Word of a public appearance by the opposition leader comes at as demonstrations have begun to quell throughout Iran, as many fear the fresh deployment of riot police and militia.

Many in Tehran seem hesitant to confront the feared Revolutionary Guard and members of the Basij militia, suggesting the harsh response wrought by hard-line President Mahmoud Ahmadinejad and supreme leader Ayatollah Ali Khamenei to large and boisterous demonstrations may have weakened the opposition's resolve.

Overwhelmed by police and left with limited alternatives, Iranian demonstrators resorted Tuesday to more subtle ways of challenging the outcome of the presidential election: holding up posters, shouting from rooftops and turning on car headlights.

Click for photos from Iran.

Severe restrictions on reporters have made it almost impossible to independently verify reports on demonstrations, clashes and casualties. Iran has ordered journalists for international news agencies to stay in their offices, barring them from reporting on the streets.

Mousavi says he was the true winner of the election. Iran's electoral commission declared Ahmadinejad the winner by a landslide, ignoring Mousavi's claims of widespread and systematic vote fraud. Mousavi has been out of sight in recent days, but a short message posted on his Web site asserted that "all the reports of violations in the elections will be published soon."

State TV reported that Ahmadinejad would be sworn in sometime between July 26 and Aug. 19.

The Associated Press contributed to this report.