Iran's supreme leader Ayatollah Ali Khamenei led the Friday prayers in Tehran for the first time since February 2012.
Move comes after a traumatic month in which the country had appeared on the brink of war with the United States and accidentally downed a Ukrainian passenger jet.
During the prayers his Friday sermon centered on the ongoing issue in the country.
He paid tributes to Major General Qasem Soleimani, describing him as the “most powerful commander of the resistance front in the region.”
According to Khamenei, Soleimani assassinations showed the United States terrorism traits.
He added that the Iran revolutionary guards maintain the security of iran. The IRGC Quds should be seen as “humanitarian organisation with human values.”
The last time Khamenei led Friday prayers at Tehran's Mosalla mosque was in February 2012 and at a time of crisis over the Iran nuclear issue.
Meanwhile, Iranian Foreign Minister Mohammad Javad Zarif has said that Tehran was ready to handover the remains of the Ukrainian passengers who were killed in the Jan.8 downing of an airliner.
Zarif made the remarks during a phone call with his Ukrainian counterpart Vadym Prystaiko on Thursday, the state-run IRNA news agency said in a report.
On his part, Prystaiko appreciated Iran for the speedy declaration of responsibility for the incident and its cooperation in all stages.
The Ukraine International Airlines (UIA) flight PS75 crashed shortly after taking off from Tehran, killing all the 176 people on board.
The victims comprised 82 Iranians, 63 Canadians, 11 Ukrainians, 10 Swedes, four Afghans, four Britons and three Germans.
Three days later, Iran's Islamic Revolutionary Guard Corps admitted that one of its missiles had downed the Kiev-bound plane due to "human error" and mistaking it for a US cruise missile.
Earlier this week, it was reported that Iran has arrested some of the people involved in the downing of the airliner.
The crash occurred on the same day Iran launched more than a dozen ballistic missiles at two US military bases in Iraq, in retaliation for the killing of Iranian Major General Qasem Soleimani in an American drone attack in Baghdad on Jan.3.