Chris Mason: Another wounding Conservative defection to Labour

Another defection. Another Conservative MP giving up on the Conservatives and crossing the floor to Labour.

Defections don't happen very often - or at least they don't in normal times - but barely days after former Tory minister Dan Poulter switched to Labour, Natalie Elphicke has too.

Little wonder there was chat before Prime Minister's Questions began that Sir Keir Starmer wanted to talk about small boat crossings in the Channel.

Natalie Elphicke is the MP for Dover.

Defections are head-spinning for Westminster, which is a tribal place.

They are a morale-lifting fillip for the party of the new arrival, and debilitating for the party the MP has left, particularly when it's from the governing to the main opposition party.

Why? They personify very starkly what an opposition party is seeking to do on a far wider scale - tempt people who recently backed the Conservatives to switch to backing Labour.

And the party political words of the defecting MP have an additional capacity to wound given their previous political home.

"The elected prime minister was ousted in a coup led by the unelected Rishi Sunak. Under Rishi Sunak, the Conservatives have become a byword for incompetence and division.

"The centre ground has been abandoned and key pledges of the 2019 manifesto have been ditched. Meanwhile the Labour Party has changed out of all recognition."

It's the sort of thing you wouldn't be surprised to hear from a career Labour MP.

But these are the words of someone who was a Conservative MP a matter of hours ago.

Labour will retain their existing candidate for Dover and Deal at the general election and Natalie Elphicke will stand down, we're told.

But Keir Starmer will delight in the pictures of him welcoming Natalie Elphicke to his side of the House of Commons.

For those in the press gallery during Prime Minister's Questions, it was quite a moment as Keir Starmer did a spot of gloating about his latest new MP.

There was a bemusement and confusion from many on the Conservative benches.

The news was announced only at midday and plenty of Tory MPs hadn't clocked that their former colleague was now sitting opposite them - directly behind Sir Keir and so in the camera shot when he was talking - rather than on their side.

A senior Conservative source wouldn't be drawn on when the prime minister learnt he had lost another of his MPs.

The source said the news "would be a surprise to her constituents who are on the front line of the illegal immigration issue".

They added that Natalie Elphicke's social media feeds were "a treasure trove of Labour's weaknesses" - the party she now sits for as an MP.

Listen to Chris on BBC Newscast on the shock defection of another MP from the Tories to Labour.