Foreign Secretary Philip Hammond says Baroness Warsi's resignation from his department over Gaza "came as a surprise".
He said the former Foreign Office minister had done a "fantastic job" but added: "I do find it surprising that she has chosen now, this particular moment, to take this stand when at long last we are seeing some relief, some progress on the issues about which she was so passionately concerned."
Asked about the criticism of other politicians, who have called for tougher language against Israel, Mr Hammond said he had to take a more "dispassionate" view on the conflict to ensure peace.
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