By Dave Burke David Cameron has warned Israel that the UK’s support isn’t unconditional in a sharp message to Benjamin Netanyahu. The Foreign Secretary made the comment amid growing concerns about the way Israel is conducting the war in Gaza. Writing in the Sunday Times, Lord Cameron said: “Of course our backing is not unconditional. We expect such a proud and successful democracy to abide by international humanitarian law, even when challenged in this way.” The Government has faced growing calls to stop sending weapons to Israel after seven aid workers – including three Brits – were killed in…