Pope Francis is to meet the Iranian president this week, and has said he hopes it will mark "a definitive step toward a more secure and fraternal world".
President Hassan Rouhani is making his first trip abroad since financial sanctions imposed on Iran by the US, EU and UN were lifted in return for the country curbing its nuclear programme.
During the meeting, the Pope and Rouhani are expected to discuss human rights. Executions in Iran – strongly opposed by the Vatican – have increased since Rouhani took office in 2013. According to the UN, Iran executed more individuals per capita than any other country in the world, and Amnesty International has condemned the execution rate as "horrifying".
Following the news that Iran executed about 700 people in the first six months of 2015, Amnesty's deputy director for the Middle East and North Africa, Said Boumedouha, said the toll "paints a sinister picture of the machinery of the state carrying out premeditated, judicially sanctioned killings on a mass scale."
According to Reuters, it is also likely that Rouhani and the Pope will discuss the plight of Christians in the Middle East. Iran is the strongest ally of Syrian president Bashar al-Assad, and global diplomats are attempting to arrange the first peace talks in two years to end the Syrian civil war.
Rouhani will lead a 120-strong delegation that includes Iranian entrepreneurs as well as the oil and gas minister and other government officials for five days in Paris and Rome. He is also scheduled to meet with French President Francois Hollande.
A week after nearly all sanctions were lifted, French and Italian officials still do not expect major deals to be signed yet during the trip. Rouhani himself has spoken of a "long road" to Iran's economic integration with the world.
Nonetheless, a senior Iranian official described the visit as "very important".
"It's time to turn the page and open the door to cooperation between our countries in different areas," the official added.
Additional reporting by Reuters.
