The European Union called on Wednesday on "all parties" to exercise "the greatest restraint" and avoid "any new escalation", after the assassination of Hamas political bureau chief Ismail Haniyeh in a strike that Iran attributed to Israel.

"The EU's principled position is to reject extrajudicial executions and support the rule of law, including within the framework of international criminal justice," said Peter Stano, spokesman for EU foreign policy chief Josep Borrell, stressing that "no country has anything to gain from a new escalation in the Middle East."