Tensions continue to build within Iran ahead of the annual celebration of the 1979 Islamic revolution on February 11. Supreme Leader Ayatollah Ali Khamenei called on Monday for unity and vowed that Iran would “punch the arrogance” on the anniversary: “The Iranian nation, with its unity and God’s grace, will punch the arrogance (Western powers) on the 22nd of Bahman (February 11) in a way that will leave them stunned.”

Washington responded to the heightened Iranian rhetoric by increasing sanctions on the revolutionary guards and lamenting the hypocrisy of Iran’s ruling regime. On Wednesday the Treasury Department announced that it was adding one individual and four companies to the list of entities affiliated with Iran’s Islamic Revolutionary Guard Corps that are targeted for financial sanctions.

The chief American representative at the International Atomic Energy Agency, Glyn Davies, told the Associated Press that it is “callous and chilling” that Iran’s government, which claims to be enriching uranium for civilian purposes, has rejected the offer to refuel its nuclear research reactor: “Why is Tehran gambling with the health and lives of 850,000 Iranian cancer patients in pursuit of ever more dangerous nuclear technology?” asked Davies.

Meanwhile, Iran’s ruthless regime made it clear that if Iran’s Green Movement opposition forces try to infiltrate the pro-government rallies tomorrow to give them an anti-government spin, then they will be jeopardizing their health and possibly their lives. Iranian police rounded up opposition activists in advance of the celebrations.

Moreover, the Iranian government has stepped up its efforts to block communication between opposition groups and the Iranian people by interfering with internet speeds and blocking text messaging services.

In addition to using street thugs to intimidate Iranian protesters, the regime also has dispatched members of the Basij militia to stage “student demonstrations” in front of the French and Italian embassies, charging the two western nations with interfering in Iran’s internal affairs.

Despite growing threats of intimidation Iran’s opposition leaders remain determined to mobilize their supporters to demonstrate tomorrow. Both sides appear to be girding for a potentially violent showdown.