TV executives have signed up former Big Breakfast presenter Lisa Rogers to help them beat Big Brother in this summer's reality TV wars.

Lisa has been in Brighton every weekend this month filming The Block, in which four couples compete to turn Brighton properties from empty shells into desirable properties in three months.

The couples, each given £25,000 to transform the three-storey houses in Vine Street, are almost half-way through filming and tempers already seem to be starting to fray.

ITV producers have been keeping tight-lipped over the programme, a cross between Changing Rooms and Big Brother.

But yesterday Miss Rogers' agent Sarah Cameron confirmed the star, former girlfriend of Royle Family actor Ralf Little, was part of the line-up.

Ms Cameron said: "Lisa wanted to get involved because it's such a great project. It did brilliantly well in Australia and I'm sure it'll be a great hit.

"She has been travelling down to Brighton every weekend and is really enjoying it. She has got friends in Brighton so when she's not filming she has been catching a few rays down by the sea."

Miss Rogers is working with property developer Nick Cowell - brother of Pop Idol Mr Nasty Simon Cowell - on the eight-week DIY series.

The show's producer Ros Ponder said the series looked set to go head-to-head with Big Brother 5, due to be presented by Davina McCall and Dermot O'Leary, when aired in July.

Ms Ponder said: "It's an amazing challenge because the couples have to continue going to work during the day and then come home to a building site at night.

"It's pretty relentless but they'll hopefully all make some money out of it.

"There has been a bit of drama but I can't say any more, you're going to have to wait and see.

"It's the obvious thing, just trying to operate when you're exhausted and having to live and work in these circumstances. It begins to put a strain on people's relationships.

"But there have been a lot of happy times too. People are making friends with each other, it's not all rows and nastiness."

Couples have been working to tight deadlines - they have to renovate a room every two weeks, starting from scratch without the basics such as skirting boards and finishing leaving it completely decorated and furnished.

Ms Ponder, who has temporarily moved to Brighton from London with most of the crew for the filming, said: "It's impossible for me to predict which couple will win. It's really close at the moment. All I will say is that they have very, very different ideas."

ITV executives are hoping viewers will be glued to their screens watching the contestants' highs and lows as they struggle to create the most popular house and walk away with £50,000 prize money.

When the show was previously made in Australia, it became cult viewing, beating Big Brother in the ratings war with millions tuning in to watch sparks fly between the stressed couples.

It has also been a huge success in Norway and is being made in the United States and Denmark.

In September, there will be a live TV auction filmed at a venue in the Brighton area where people can bid for their favourite house.

Each couple will walk away with any profit made above the reserve price on their property.

Ms Ponder said the production company, RDF Media, was planning to open up the finished houses a month before the auction so people could look around them before they went on sale.

She said ITV also planned to hold a competition where one viewer would win enough cash to take part in the auction and use a professional bidder.