US President Donald Trump hailed a "tremendous day for the Middle East" as he and regional leaders signed a declaration meant to cement a ceasefire in Gaza, hours after Israel and Hamas exchanged hostages and prisoners. Trump made a lightning visit to Israel, where he lauded Prime Minister Benjamin Netanyahu in an address to parliament, before flying to Egypt for a Gaza summit where he and the leaders of Egypt, Qatar and Turkey signed the declaration on Monday as guarantors to the ceasefire deal. "This is a tremendous day for the world, it's a tremendous day for the Middle East," Trump said as more than two dozen world leaders sat down to talk in the resort of Sharm el-Sheikh. He...