Braxton Carter, T-Mobile US’ CFO, described Iliad’s bid for the US operator as “inadequate” but indicated a higher offer might be viewed more positively, according to The Wall Street Journal.

Carter commented at an investor conference that Iliad’s late-July offer to buy 57 per cent of the fourth-largest US operator for $15 billion in cash was “very flattering” but “a very inadequate value proposition.”

However, he went on: “I think rarely people come with their best bid to start”. He also praised Iliad’s founder Xavier Neil as a “very impressive entrepreneur”.

This contrasts with last week’s comments from Deutsche Telekom CEO Timotheus Hottges who adopted a dismissive tone towards the Iliad offer.

“We’ve always said that we’re open to transactions which increase the value,” he said, before swiping: “we don’t have such an offer at this point.”

Iliad said it does not need to increase its bid after T-Mobile US’ longterm suitor Sprint dropped out of the race because of regulatory concerns about merging the third- and fourth-largest US operators.

However, there have been suggestions that Iliad is working on a refreshed offer. The other possibility is a new bidder stepping forward, such as satellite TV broadcaster Dish Network or one of the country’s leading cable television operators. An alliance between a group of such players is another possibility.