Another letter goes in — how close is Boris to 54?

Nick Gibb has become the latest Tory MP to declare that he has submitted a letter of no confidence in the Prime Minister to Graham Brady. The former schools minister writes in the Telegraph that ‘to restore trust, we need to change the Prime Minister’.

Gibb’s letter will worry the Johnson operation because he is not a usual suspect. Yes, he left government in last September’s reshuffle. But he has hardly been a serial critic since then. If parliamentarians like him are coming out publicly, No. 10 will worry about how many more are submitting letters behind the scenes.

The whole question of how many letters are actually in, as opposed to being publicly declared, is shrouded in mystery. The only person who knows for sure is Graham Brady, and he’s not telling. But if we take the rule of thumb suggested to me by one of those central to the effort to save the PM that for every two letters publicly submitted another three have come privately, then we are in the early 30s in terms of letters .