Enrique Mora, the EU coordinator in Iran nuclear talks and deputy secretary-general of the European External Action Services, the EU's foreign ministry, plans to attend Raisi's inauguration. The event is set to take place less than a week after Iran attacked an Israeli-managed ship of the coast of Oman, killing a citizen of Romania - an EU member state, and a British national.
Israel called on the EU to cancel its participation in the event.
Foreign Ministry Spokesman Lior Haiat said “the decision of the European Union to send a senior representative to the swearing-in ceremony of the ‘Butcher of Tehran’ is puzzling and shows poor judgment.”
Raisi’s nickname refers to the former judge’s role in the execution of thousands of Iranian dissidents, which earned him US sanctions for human rights violations.
Calling the attack on the Mercer Street an act of state-sponsored terror, Haiat said EU attendance at Raisi’s swearing in “gives legitimacy to the Iranian attack and the policy of aggression of the ayatollahs’ government.”
Former EU high representative for foreign affairs Federica Mogherini attended the inauguration of Iran's departing president, Hassan Rouhani.
However, the current ceremony is taking place after a nearly two-months break from indirect negotiations between Iran and the US to return to the 2015 nuclear deal.
Mora's visit to Iran is meant in part to break the impasse and revive the talks, The Wall Street Journal reported.
Some of the European parties to the 2015 Iran deal - the UK, France and Germany, known as the E3 - objected to sending Mora to the inauguration, but none of the non-E3 European Union member states opposed it, according to The Wall Street Journal.
Earlier Monday, British Prime Minister Boris Johnson said on Monday that “Iran should face up to the consequences of what they’ve done.”
"This was clearly an unacceptable and outrageous attack on commercial shipping. A UK national died. It is absolutely vital that Iran and every other country, respects the freedoms of navigation around the world and the UK will continue to insist on that,” Johnson added.
The US, UK and Romania have said they are coordinating a response to the Iranian attack.