KEITH Miller is to step down as chief executive of Miller Group by the end of March after leading the business for more than 20 years.

Mr Miller, who turns 66 next month, had joined the company in 1975 and went on to run the mining and development arms before becoming the group head in 1994.

Miller Group said it will not be replacing him as chief executive.

Instead overall management responsibility is going to be passed to the bosses of its mining, developments and housing arms.

Phil Miller, who is no relation to the founders which included Keith's father, heads up the developments business.

Chris Endsor runs Miller Homes while Neil Brown is in charge of the Miller Argent opencast mining venture in south Wales.

It is understood Keith Miller is not planning to retire but felt it was the right time to leave the group having led it through the financial crisis and a major restructuring in more recent years.

That restructuring saw the group pass from family control in 2011 to be majority owned by GSO Partners, part of private equity giant Blackstone Group.

Other shareholders include Royal Bank of Scotland's West Register Investments, Lloyds Banking Group's investment arm Uberior Equity and Noble Grossart Investments along with management and family members.

On his decision to step down Mr Miller said: "We have strong management teams in place in Miller Homes, Miller Developments and Miller Mining, each of which is led by its own chief executive.

"I am looking forward to being able to report further impressive performance from Miller Homes and our other businesses when we announce our final results for 2014 in a few weeks' time.

"The group has experienced tremendous growth over the past three years and the time is right to pass the leadership of our businesses to the respective management teams."

Mr Miller is said to be keen to pursue other business interests but it is not yet known whether that may include building up a portfolio of non-executive positions.

The company was founded in 1934 by architect James Miller and his brothers John and Lawrence.

It became Edinburgh's largest housebuilder prior to World War Two.

The war led to Miller moving into construction and on cessation of hostilities it resumed housebuilding activities eventually extending its operations into England.

Keith, the son of John Miller, came into the family company after a spell at Taylor Wimpey and worked his way up the ranks.

When Mr Miller leaves it means no family members will be involved in the executive decision making at the group.

According to a spokeswoman for Miller Group the change at the top will not affect the location of the current head office function in Edinburgh.

The possibility of Miller Homes reviving its intention to float on the stock exchange is also still under consideration.

A spokeswoman confirmed that it "remains an option" which is being looked at.

However no indication was given on when the house building arm, which is targeting 2,750 annual completions in the medium term, might look to get onto the public markets.

It had shelved initial plans for a flotation, where it hoped to raise around £140 million and be valued at £450m, in October last year citing the volatility of the market at that time.

The Miller Construction business was sold to Galliford Try last summer.

In August Miller Group said turnover from continuing operations had grown 23 per cent from £168.2m to £206.9m with profits more than doubling to £8.3m.

Net debt was also shaved by £29m to £169.4m.