The EU will slap fresh sanctions on President Bashar al-Assad's regime next week and clarify the rules on insuring items embargoed for delivery to Syria, including arms, EU diplomats said Wednesday.

European Union foreign ministers meeting in Luxembourg on Monday are expected to announce an asset freeze and travel ban on five Syrian firms and one individual, in what will be the 16th round of restrictive measures against the Assad regime.

They will also state "in black and white" that insuring arms deliveries to Syria is banned under an arms embargo decided last year, one source said.

The wording of the statement, which diplomats said was agreed Wednesday by ambassadors of the 27 EU nations, follows an incident this week involving a British-insured Russian cargo ship, allegedly carrying attack helicopters for Syria.

The United States alerted Britain to the consignment and British security services told insurers Standard Club that providing insurance for the shipment would breach EU sanctions, reports said.

Standard Club then cancelled insurance for the ship as well as others in the fleet owned by Russian cargo line Femco, forcing the vessel to head home.