Germany’s Social Democratic Party leader Sigmar Gabriel has apologised after calling Israeli policy towards Palestinians an “apartheid regime” following a visit to Hebron in the West Bank.

Gabriel, one of three possible Social Democratic challengers to Chancellor Angela Merkel in next year’s general election, later admitted he had used a “very drastic formulation,” but said that he was only describing the situation as experienced by people in the town.

"For Palestinians this is a lawless zone," Gabriel wrote on his Facebook page. "It is an apartheid regime, for which there is absolutely no justification."