The 28 anxious EU leaders are gathering in the Bulgarian capital for discussions over dinner on how to salvage the nuclear deal and European business dealings with Iran from Trump's sanctions.
On Wednesday, French energy group Total said it would pull out of a multibillion-dollar gas project in Iran if it couldn't secure a waiver from the United States sanctions.
Other companies which have warned they would wind down business in Iran following reinstated sanctions include German insurer Allianz, Siemens and Danish oil product tanker operator Maersk Tankers, previously owned by the Maersk conglomerate.
At dinner talks in the Bulgarian capital, European Union leaders were briefed on possible incentives to keep Tehran in the nuclear agreement despite the USA pulling out.
Despite pressure from Washington, Macron insisted European countries are committed to the deal with Iran.
Merkel defended the deal in remarks to the Bundestag before the travelled to Sofia. "We promised to take political measures allowing our enterprises to remain in Iran", TASS cited Macron as saying.
'This agreement is everything other than ideal, but Iran is, according to all the knowledge of the worldwide nuclear authorities, sticking to the commitments of the agreement'.
German Federal Chancellor Angela Merkel criticized in the lower house of parliament (Bundestag), the withdrawal of the USA government from the nuclear agreement with Iran.
AFP reported that France's foreign minister condemned the United States for reimposing sanctions against foreign companies trading with Iran, labelling the move "unacceptable" in comments that expose the deepening rift between Washington and its European allies on the issue.
"The 2015 agreement needs to be completed by a nuclear agreement beyond 2025, an agreement on ballistic activities and (Iran's) regional presence", Macron said.