The news that Chuka Umunna is getting paid £451 an hour to chair a new centrist think tank will go down very well indeed with some of his Labour colleagues. It's not so much that those MPs are just delighted for Umunna, as it is that they can use his £65,000 salary to undermine the chances of the new centrist party that this think tank might be working for.

The Labour leadership is naturally worried about the idea of a breakaway centrist party, as it could rob Jeremy Corbyn of his chance to become Prime Minister at the next general election. But the Corbynite attack line against such a party being merely an establishment stitch-up is pretty good. And Umunna's new job plays perfectly into that attack line. If a new party is full of high-earning, metropolitan types, then it won't cause political shockwaves across the country, or so goes the attack argument, anyway.

It's not just Corbyn supporters who use this line, though. Those centrist Labour MPs who think it is best to stay in the party are also trying to wear down their wavering colleagues using a number of arguments, including that the new centrist party would appear to be an establishment stitch up. Once again, some of their colleagues may find Umunna's salary underlines this, especially for those Labour MPs representing very poor seats. Others have been put off by their friends telling them that their constituency will always elect a Labour MP, and so by leaving the party, they are guaranteeing that a Corbynite will replace them as the MP, which will further consolidate the Left's power.

Presumably Umunna's think tank will partly be trying to address some of these problems. But it hasn't got off to a great start at doing that.