The BBC must serve its regional audiences better, the culture secretary said as he announced a radical shake-up of the broadcaster's operations.

Revealing the UK Government's White Paper on the company's future, John Whittingdale revealed the BBC would have to commit to improving its offering to "under-served audiences" across the UK.

This includes black and Asian audiences, as well as those in Scotland, Wales and Northern Ireland.

Under the proposals, the BBC Trust will be abolished and Ofcom will be the external independent regulator of the broadcaster.

In addition, a new "unitary board" will be established, which will consist of 12 to 14 members.

BBC director general Tony Hall said a Scottish "sub-board" would be set up to ensure improved services north of the border.

Writing to Scottish culture secretary Fiona Hyslop, Mr Hall said Scotland would also be made a "centre for excellence for factual programming" and a Glasgow-based comedy commissioner would be appointed.

The broadcaster also promised to form new partnerships with creative agencies in Scotland and nurture local talent via its "writers' rooms" and targeted funding.

Meanwhile, the BBC's news output will be reviewed in a bid to find "the right balance between the provision of pan-UK news and dedicated news services in the nations."

Mr Hall wrote: "Audiences have told us, and the BBC Trust, that they think we need to do more to capture distinctive stories from across the UK and share them across the country, as well as doing more to reflect the changing nature of the UK and support democracy and culture.

"We have heard these concerns from audiences and I have also heard directly from you and your colleagues.

"And as a result we have set ourselves a clear creative challenge: to tell the story of a changing UK."

Other reforms put forward in the White Paper include a new requirement to provide "distinctive content" rather than focusing on chasing ratings.

Fewer in-house shows are likely, as the BBC must remove the in-house guarantee for all television content spend - except for news and news-related current affairs - to open programme-making to greater competition.

Any employees earning more than £450,000 per year will have their earnings published in a move towards transparency.

Viewers who catch up on BBC shows online will have to buy a TV licence, closing the so-called "iPlayer loophole".

Mr Whittingdale told MPs: "The BBC is and must always remain at the very heart of British life. We want the BBC to thrive, to make fantastic programmes for audiences and to act as an engine for growth and creativity.

"Our reforms give the BBC much greater independence from Government in editorial matters, in its governance, in setting budgets and through a longer charter period.

"They secure the funding of the BBC and will help it develop new funding models for the future.

"At the same time, these reforms will assist the BBC to fulfil its own stated desire to become more distinctive and to better reflect the diverse nature of its audience."

Mr Hall said the White Paper "delivers a mandate for the strong, creative BBC the public believe in. A BBC that will be good for the creative industries - and most importantly of all, for Britain".

TV writer and producer Armando Iannucci, who has been a regular contributor to the broadcaster since working with BBC Scotland in the 1990s, was relieved with the outcome of the White Paper.

He posted on Twitter: "No cuts to BBC budget, no interference in schedules, and majority on Board not appointed by Govt. This is good to hear."

John Nicolson MP, the SNP's culture spokesperson, said: ''It is encouraging that UK culture secretary John Whittingdale has acknowledged that audiences in Scotland are underserved by the BBC - he is right to do so. The corporation must reflect the diversity of audiences around the UK.

"It is vitally important that we have the opportunity to fully debate the proposals as many Tories still appear ideologically opposed to public service broadcasting. Those of us who support it need to be constantly vigilant that the BBC's vital independence is not watered down by stealth.

''At its best the BBC is unsurpassed as a broadcaster. But too often - and particularly in some of its news provision - it has fallen short of the high standards that people in Scotland expect.

''It is clear the BBC itself now recognises it has to 'up its game', and I welcome the fact that it is now piloting a distinctive Scottish news programme with national and international news.

''There is no doubt that the broadcast journalism and production talent is there to deliver a superb, new news service. But for it to be a success, it is up to the BBC to ensure it is resourced properly.''