Union bosses have warned that some unscrupulous shipowners may seek to recoup the extra costs of diverting vessels away from the Suez Canal.
This could mean delaying crew changes as ships head around the Cape of Good Hope after the 20,388-teu Ever Given (built 2018) caused a huge vessel jam following its grounding in the canal on 23 March.
International Transport Workers' Federation (ITF) general secretary Stephen Cotton welcomed the refloating of the giant boxship and praised the seafarers involved in the effort.
