At the High Court, the Scottish media group argued that the pair had no right to adopt the ITV brand.

SMG's calls for an injunction to prevent the move were turned down.

However, Granada and Carlton did agree to an undertaking to pay SMG compensation if they failed to prove they had the right to the name.

Under the order, the two groups would also have to make payments to fellow independent television groups Ulster and Channel.

'Hijacked'

SMG added: "We took this action to protect the interest of our shareholders, and indeed our viewers and advertisers, as we believed that the ITV name was in danger of being hijacked by Carlton and Granada."

But Carlton signalled that the merger partners were not planning to back down over the issue.

When asked whether Carlton and Granada aimed to use the ITV plc name in future, spokesman Peter Rushton told BBC News Online: "Absolutely. We will be having further discussions with SMG."

SMG argues that the ITV name is a collective one that belonged to all 15 of the original regional franchisees - similar to a trading body - and as a result cannot be taken on by any one member.

The company has said it will be seeking further talks with Carlton and Granada as there are "still some concerns over their licences" as the companies do not own the ITV name.

This latest hurdle is not the first bump along the way to the planned �4bn merger.