Quitting whips hit Labour's ability to be effective Opposition

Two weeks ago in Liverpool, Jeremy Corbyn was re-elected Labour Leader with a thumping majority.

He called for party unity and said he would "reach out" to different parts of the Parliamentary Labour Party. Those who opposed him accepted they had to tame their vocal criticism.

It almost looked as if, after a year of turmoil and disunity, Labour might have called a truce on all the infighting.

How wrong that was to be.

Today, two whips have resigned from the shadow whips team after the sacking of their boss Rosie Winterton and there could be more to come.

So how have we arrived here again?

Well, far from reaching out, Mr Corbyn has instead tried to tighten his control of the party.

His reshuffle, branded "divisive" by the Parliamentary Labour Party chair, saw the promotion of loyal supporters such as Diane Abbott and Shami Chakrabarti and few of those vocal critics.

He has given no ground, yet, on elections to the shadow cabinet, something many MPs want.

And many suspect he is trying to gain control of the National Executive Committee, the party's governing body, by getting Jon Ashworth MP removed from it.

Adding all of that to the sacking of the shadow chief whip Rosie Winterton and maybe it isn't a surprise that Labour MPs are "livid", as one put it to me.

Lots of MPs, and particularly those in the whips office, have been fiercely loyal to Ms Winterton. For many of them, she has been the unifying force over the past year.

So these resignations were expected - they were being discussed since Thursday.

If more follow it poses big practical problems for Mr Corbyn.

The whips are vital to ensuring the party can function in Parliament. If they resign en masse, Labour's ability to prove an effective opposition takes a severe hit and at a time it is most needed.

Labour's year of discontent continues…