The Conservatives have criticised culture secretary Tessa Jowell for indicating that the BBC will continue to be funded by the license fee for the next 15 years.

In an interview with the FT, Jowell said she was not planning any radical changes to the structure of the BBC when its charter comes up for renewal in 2006.

But her comments sparked anger from the Conservatives. Shadow culture secretary Tim Yeo said her position could work against the interests of both viewers and broadcasters.

The BBC's main source of funding is the £2.3 billion a year it receives from license fee payers, but Jowell appeared to rule out other options such as privatisation, subscription charges or advertising revenue.

"When I say that this is a no holds barred charter renewal it's a renewal rather than a deconstruction of the existing architecture.

"The prospect of the UK without the BBC funded by the licence fee is anywhere between improbable to impossible because the BBC is one of the most loved and trusted UK institutions," the culture secretary told the newspaper.

She also said it was "highly unlikely" that the government would consider privatising the BBC.

But she did not rule out completely the possibility of some reform, saying she would not get "boxed in" on policy options.

"Sometimes in order to reach the right decision you have to think the unthinkable."

And in words that will hearten the corporation, there was warm praise for the BBC's work in covering the Golden Jubilee events.

"I am particularly proud of the BBC for everything they have done both in Music Live and in broadcasting and producing the concerts. It's an example of the BBC at its very best: what we all remember it excelling at throughout our lives," she said.

Jowell linked the BBC's success with the government's recently published proposals to relax restrictions on media ownership.

"It's because the BBC has been so consistently a benchmark for quality in broadcasting that we can afford to be as ambitious as we are in deregulating the rest of the industry as people will still have to match the BBC's quality if they want to get a decent audience share and reach."

The minister also said the government would stick to its manifesto commitment not to privatise Channel 4.

But the Conservatives said the government risked failing to keep up with the rapidly changing media sector.

"In the 10 years since the last charter renewal the whole television sector has radically changed," said Tim Yeo.

"To simply dismiss the alternative possibilities before the debate has taken place not only shows a closed mind but may also work against the interests of viewers and broadcasters.

"The BBC license fee is in effect a television tax which all viewers must pay even if they never watch BBC programmes. New technology offers the opportunity for different payment methods that should be examined when the charter renewal takes place in 2006," he said.