A former television executive, Lord - formerly Gus - Macdonald is Tony Blair's fourth transport minister in two years.

Seen as a proven problem-solver after years in industry, he moved up in July from his post as a junior minister in the Scottish Office to replace Helen Liddell in the deputy prime minister's giant department covering transport, the environment and the regions.

Lord Macdonald, formerly the front man of Channel 4's Right to Reply programme, inherited a tricky, high-profile brief.

Public impatience over gridlocked roads, tube line closures and the failing rail network have all remained hot topics for headline writers in recent months.

Mr Prescott's department has been criticised by MPs for making little tangible difference to the nation's transport system.

Downing Street announced Lord Macdonald's appointment saying: "The prime minister believes that he is someone of real experience, real drive and achievement who will support John Prescott in tackling the transport problems inherited from the last government."

The fact he is an unelected life peer led some to question the prime minister's faith in his 416 Labour MPs.

But the move to increase Lord Macdonald's powers over his brief - handing him day-to-day responsibility - shows the faith in his abilities at the highest level.

From red Clydeside to red buses

Lord Macdonald left school at the age 15 to begin work in the Glasgow shipyards as a fitter.

As a young man, Lord Macdonald was a radical left-winger, and after leaving the shipyards after eight years he became circulation manager for the left leaning journal Tribune before taking his first step into journalism as a feature writer at The Scotsman.

After producing and editing the documentary programme World in Action in the early 1970s, he eventually became the head of Scottish Television Enterprises and the chairman of the Scottish Media Group.

Although Lord Macdonald markedly increased the turnover of Scottish TV he also presided over large-scale job losses.

Lord Macdonald, who is close friends with both Gordon Brown and Donald Dewar, was created a peer in 1998, and was appointed to the Scottish Office in the same year, the last appointment of Tony Blair's 1998 re-shuffle.

His appointment was seen as the latest round in the "Tony's cronies" saga by the Tories. Some Scottish Labour MPs were disgruntled at his elevation to office which saw many longstanding MPs passed-by.

Lord Macdonald was formerly active in left-wing politics but on his appointment to the government in 1998 he revealed his political activism had waned: "I became non-political about 25 years ago and I have not carried a party card since," he said.

On coming to office he sold his shares in Scottish Media Group netting nearly £800,000.

He was seen as a success at the Scottish Office, particularly for his role in saving Kvaerner Govan shipyards.