Iran attacks 'reinforce hatred' for US, Saudi: leader

The attacks in Tehran this week will only "reinforce hatred" for the United States and Saudi Arabia, Iran's supreme leader said on Friday at a funeral for those killed.

"Such acts will have no other result than to reinforce hatred for the US government and its agents in the region, like the Saudi (government)," Ayatollah Ali Khamenei wrote in a message of condolence to the families of the dead.

Wednesday's attacks on Tehran's parliament complex and the shrine of revolutionary leader Ayatollah Ruhollah Khomeini killed 17 people and wounded more than 50.

They were the first attacks in Iran to have been claimed by the Islamic State group.

The funerals for those killed began on Friday morning in Tehran with a ceremony in parliament.

After prayers, a procession will leave Tehran University for the Behesht-e-Zahra cemetery, near the Khomeini mausoleum 13 kilometres (eight miles) south of the Iranian capital.

The intelligence ministry said the attacks were carried out by five Iranian men who had joined IS and travelled to their bastions in Iraq and Syria before returning home.

Iran's elite Revolutionary Guard has accused regional rival Saudi Arabia of involvement in the attacks.

But Intelligence Minister Mahmoud Alavi said "we still cannot judge that Saudi Arabia has had a role in this terrorist incident".