TEHRAN: Iran's President Hassan Rouhani on Monday said Iran-Europe relations are unlikely to suffer over the recent execution of a dissident, following European condemnation and the postponement of a major business forum.

Ruhollah Zam was hanged on Saturday after Iran's supreme court upheld his death sentence passed in June over his role in protests during the winter of 2017-18, among other charges, such as espionage.

"I don't think this issue will harm relations between Iran and Europe," Rouhani said in a press conference.

The outcry over Zam's execution comes at a delicate time, as European powers are seeking to reinvigorate the 2015 Iran nuclear deal when US President-elect Joe Biden takes office early next year.

The accord has been on life support ever since President Donald Trump withdrew the US from the deal and reimposed crippling sanctions on Iran in 2018.

On Saturday, the EU condemned Zam's execution in the "strongest terms" and emphasised its "irrevocable opposition to the use of capital punishment".

The three-day Europe-Iran Business Forum, due to kick off on Monday, was also postponed by organisers after France said its ambassador to Tehran, as well as those of Germany, Austria and Italy, would not attend over the "barbaric and unacceptable execution".

Britain, France and Germany are parties to the nuclear accord, alongside China and Russia.

"The Europeans have always been sensitive regarding some issues, and so are we" regarding Europe, Rouhani said.

"We do have execution sentences in this country, it is part of our law. Why be so sensitive regarding a specific individual?" he added. "It conveys a sense of meddling" in Iran's affairs.

Iran on Sunday summoned the ambassador of Germany, which currently holds the EU's presidency, as well as that of France, to protest the bloc's and the respective countries' condemnations of the execution.

Zam was granted political asylum in France and reportedly lived in Paris before his arrest last year by Iran's Revolutionary Guards, who claimed he had been "directed by France's intelligence service".

In a Monday statement, the United Nations rights chief Michelle Bachelet said she was "appalled" by Zam's execution and urged Tehran to halt its "alarming and increasing" use of death penalty.

The US Secretary of State Mike Pompeo also denounced the hanging as "barbaric" in a tweet.