Iran's state TV reported that more than 130 high-ranking officials from various countries and worldwide organizations attended the ceremony in Tehran.
Discussions over United States foreign policy vis-à-vis Iran are continuing as we speak.
Union Road, Transport, Highways and Shipping Minister Gadkari represented India at the oath taking ceremony.
A Hamas delegation has arrived in Tehran to participate in Iranian President-elect Hassan Rouhani's swearing-in ceremony on Saturday, Anadolu Agency reported.
The inauguration ceremony of reelected Iranian President Hassan Rouhani was held in Tehran on Saturday.
In response, President Rouhani highlighted the importance of the security of Northeast Asia, saying Iran will support the stability and development of Asia.
Addressing religious, military and political leaders, Supreme Leader Ayatollah Ali Khamenei, Iran's top authority, prayed for "the success of a worthy person".
Under Rouhani's watch, Iran reached a landmark deal with six major powers in 2015 under which it agreed to curb its nuclear activities in exchange for the lifting of sanctions which had been in place for a decade.
In recent weeks, the United States has imposed new sanctions on Iran nationals and entities, accusing it of breaching the nuclear deal, allegations that Iran denies.
Trump, who during his election campaign previous year called 2015's nuclear agreement "the worst deal ever", signed new sanctions into law on Wednesday, along with measures against Russian Federation and North Korea. It also imposes mandatory sanctions on the already-sanctioned Iranian Revolutionary Guard Corps ("IRGC") and the IRGC-Quds Force (and their officials, agents, and affiliates) for their support for global terrorism.
Iranian officials say they have prepared a 16-point document for how they will respond to the new sanctions, without giving details.
For Rouhani, who had hoped his second term would focus on rebuilding the stagnant economy, "it's unfortunate timing", said Ellie Geranmayeh, an Iran analyst with the European Council on Foreign Relations. Rouhani has to announce his new cabinet members to Parliament within 14 days.