The upcoming non-aligned summit in the central Iranian province of Isfahan on August 30-31 has provided an opportunity for PM Manmohan Singh to honour President Mahmoud Ahmadinejad's long-pending invitation for a bilateral visit to that country.
Energy ties and transit and connectivity issues, apart from regional factors such as Afghanistan, are likely to weigh heavily on the bilateral agenda.
The PM's visit is taking place at a time when the West, including the US, and Israel are trying to put Iran in a squeeze for its nuclear programme.
Though India has reduced oil import from Iran, Tehran remains a key factor in New Delhi's strategic calculations. This is because Iran is India's only surface access to Afghanistan and Central Asia.
New Delhi has also taken great pains to explain that its relations with Iran are "neither inconsistent with its non-proliferation objectives", nor in contradiction with the ties India has with "friends in West Asia or with the US and Europe".
India stands for a peaceful resolution of the Iran nuclear question, but insists that Tehran honour its commitment under the nuclear non-proliferation treaty.
External affairs minister SM Krishna will be in Iran on August 28 and 29 to take part in the non-aligned foreign ministers' meeting, ahead of the summit.
It was in 2001 that an Indian Prime Minister -Atal Bihari Vajpayee - last visited Iran, and Ahmadinejad had a stop-over in New Delhi on his way to Colombo in 2008.