In a shock move, Chuka Umunna, Shadow Business Secretary has just sensationally announced that he is withdrawing his candidacy bid for Leader of the Labour Party. 

A statement, released by Mr Umunna states that he has become increasingly uncomfortable with the level of attention and pressure he has come under since he announced his intention to stand. He added that he had not found this to be a comfortable experience and offered his sincere apologies to those people who had supported and encouraged him over the last week. He also commented that he had been worried about the fact seeking this new role would have had an unknown impact on those who were closest to him. 

There is speculation from some political commentators that Mr Umunna had become aware of "negative press" that may be about to come to light this weekend, but as yet, this is unconfirmed.

He had appeared in public for the first time, with his girlfriend Alice Sullivan, an employment lawyer last weekend.

He has said he will remain in the Shadow Cabinet and will be committed to playing a "full role" now and in the future.

The withdrawal has already caused anger and consternation amongst the people who have supported him and there are now concerns that this could actually end up deepening the crisis within the Labour Party, that occurred after their defeat in last week's General Election.

Mr Umunna's withdrawal leaves the party with four candidates in the running, they are:

Andy Burnham 

Liz Kendall 

Yvette Cooper

Mary Creagh

Creagh's announcement she would stand came as a surprise.

The Wakefield MP is also Shadow International Development Secretary and is standing as she wants to "win back Middle England" for the party.

Favourite for the leadership now is certain to be Andy Burnham, who missed out at the last Labour leader election in 2010 to both the Miliband brothers.

For now though, Westminster is trying to catch its breath after the rising star of the party's sensational announcement. More to come on this story as it unfolds during the weekend.