14 minutes ago Henry Zeffman, Chief political correspondent, Chris Mason, Political editor, Iain Watson, Political correspondent and Nick Eardley, Political correspondent PA Media That is the question that matters after Sir Keir Starmer's speech. Was it enough to avert a challenge to the prime minister's leadership less than two years after he won a landslide general election victory? In the first instance, the person whose answer to that question matters most - and this would have sounded like a strange joke just two days ago - is Catherine West. West, until the last 48 hours a relatively unknown former minister, told the BBC on Saturday night she was willing to try to force a leadership contest if no one else came forward. But having heard the prime minister's speech, she is standing down from running as a stalking horse candidate and trying to trigger a formal leadership contest right now.…