By Lizzy Buchan Rishi Sunak called an emergency Cabinet meeting tonight as expectations mount that the UK is poised to join military strikes against Houthi rebels in Yemen. The Prime Minister briefed top ministers on the escalating situation after a string of attacks on ships in the Red Sea. Foreign Secretary David Cameron was seen entering No10 just before 8pm and Commons Speaker Sir Lindsay Hoyle was also summoned to a Whitehall briefing. Labour leader Keir Starmer and Shadow Defence Secretary John Healey are also understood to have been briefed. Downing Street refused to comment last night …