On Thursday, President Rouhani directed Iranian Interior Minister Abdolreza Rahmani Fazli to conduct an investigation to determine the cause of the fire and the ensuing collapse of the building and issue a report on the incident the soonest.
Offering his deep condolences to the Iranian nation over the tragic event, the president further ordered the minister to take all necessary actions to address the immediate needs of the injured.
Rouhani also urged all relevant governmental organizations to compensate for those affected.
Tehran Mayor Mohammad Baqer Qalibaf said between 20 to 25 people are believed to have been trapped under the rubble.
The fire began on Thursday morning at the Plasco building in Tehran and the over 50-year-old high-rise collapsed after a few hours.
Firefighters are now searching to take out their comrades remaining under the rubble.
Police has blocked off streets around the 17-story structure, which was among the first high-rises built in the Iranian capital.