Obituary: Lord Walker of Worcester

PETER Walker had the distinction of serving in the Tory cabinets of Edward Heath and, for a decade, Margaret Thatcher. It was a unique achievement.

One of his most significant appointments under Thatcher was as energy minister, which thrust him into a central position throughout the vitriolic miners' strike in 1984-85. He was convinced the strike would be won and Arthur Scargill and the National Union of Mineworkers would be defeated.

Although he was often at odds with Thatcher over the management of the strike – and many other social issues – Walker was invaluable to her throughout the dispute.

He was a cool operator and preserved a united cabinet, but carefully countered the aggressive tone of the miners' spokesmen with some well-reasoned statements. Walker, astutely, often made impassioned pleas over the heads of strike leaders to ordinary trades unionists.

He led a calculated campaign and wrote at the time: "The public understandably demands that the government maintain the rule of law. That can only be done in a genuine democracy by the police and the courts. The mob has failed to close one colliery that has voted to work."

Peter Edward Walker was the son of a greengrocer and educated at Latymer Upper School. He left school at 16 and started work as an insurance salesman. In the mid-1950s, he borrowed 50 from his father and set up his own financial business. He met Edward du Cann and the two (both soon to become leading lights in the Conservative Party) pioneered the fledgling unit trust movement by founding the Unicorn Group.

In 1964, he joined Jim Slater in founding Slater Walker, a dynamic (if, at times, controversial) City institution which pursued some forward-thinking financial practices. Walker remained deputy chairman until 1970, when he became a minister. He therefore escaped the damage to the firm's reputation after its ill-advised bid for Hill Samuel, the run on the secondary bank sector and the collapse of the company in 1975.

In tandem with his City career, Walker maintained an increasingly high profile in the Tory party. He was chairman of the Young Conservatives in 1961 and became MP in the safe seat of Worcester – which he held until he left politics in 1992. He managed Heath's bid for the leadership in 1965 after Sir Alec Douglas-Home resigned and was rewarded in 1970 with the Ministry for the Environment, where he reorganised English local government. He kept a weather-eye on policies and is credited with campaigning for the sale of council houses many years before Thatcher.

After Thatcher became prime minister, she considered it prudent to have him in the cabinet, rather than causing trouble on the back benches. She had always admired Walker's abilities, but thought of him as a wet and certainly not "one of us". She put him in charge of agriculture, where he had an intriguing verbal conflict in the House with Tam Dalyell. The Linlithgow MP had asked a complex question, to which Walker gave an in-depth reply. Dalyell knew the minister was providing a pat answer and impishly asked a concise supplementary: "Why, sir?" Walker was left delving into his notes.

In 1983, Walker became energy secretary and was immediately forced into the front line of UK politics. The miners' strike was a bitter and divisive issue that created much acrimony throughout society. Although Walker did not get on particularly well with Ian MacGregor, the chairman of the National Coal Board, Walker proved himself to be a wily manipulator of the media and strenuously advised Thatcher not to start civil proceedings against the mining unions.

Walker maintained private links with Norman Willis, the TUC general secretary, which helped to smooth relations after the strike collapsed.

But the year was a challenging one for Walker. The very public battles between the police and miners were not his idea of social democracy and such oddities as MacGregor's emerging from the Ellersly House Hotel in Edinburgh's Murrayfield with a brown bag over his head only further hampered their working relationship.

Walker resigned six months before Thatcher left office. He was given a life peerage and became a director of several City firms. He flirted with becoming chairman of Robert Maxwell's communications company, but wisely withdrew. Walker had a nose – in politics and business – of knowing how to avoid trouble. He was, indeed, a great survivor.

Peter Walker is survived by Tessa Pout – whom he married in 1969 – and three sons and two daughters. Their son Robin was elected Tory MP for Worcester, his father's old seat, on 6 May.