'Big Brother' housemates will be forced to nominate each other live on air this week.

The remaining 12 contestants on the Channel 4 fly-on-the-wall series will be asked to name the two people they want to face the public vote - and may have to do so in front of the rest of the house.

A source said: "Bosses are always wanting to shake things up and what better way than to pile on the drama by forcing everyone to air their grievances not only to the viewers but to the people they're complaining about. Everyone expects sparks will fly and it'll make great live TV."

It is expected the housemates will be given just a few minutes notice before being told of the live nomination plan on Wednesday (24.06.09).

On Friday, (19.06.09), American student Cairon became the second official housemate to leave following Sophia the week before.

Both contestants lost the public vote against posh Freddie, who is now favourite to win the series.