Ministers should be allowed to remain in post for the full length of a parliament if they are doing a good job, former energy minister Brian Wilson has suggested.

The Cunninghame North MP, who left government in the reshuffle earlier this month, says that a ministerial appointment should be seen as a contract for up to five years.

The current system of a major annual turnover of the lower ranks of government plays into the hands of civil servants, he fears, who are able to use their superior knowledge to push rookie ministers around.

"The civil service - although there are many admirable officials who would prefer to deal with ministerial stability - is institutionally dependent on the reshuffle ritual in order to maintain the upper hand in making and implementing policy," Wilson claimed in an article for the Telegraph.

"Within 24 hours of my standing down as energy minister last week, positions which I had established against the advice of officials were being quietly reversed."

Having held five government posts in six years, Wilson contends that a longer spell in the same job would allow ministers to get their feet more firmly under the table and exert their influence.

Ministers should "stay in their jobs long enough to become reasonably expert and therefore in a position to both mould policy and challenge recommendations" he says.

"My basic reform would be to regard a ministerial appointment at the beginning of a parliament as effectively a contract for up to five years," added Wilson.

"If the minister was doing a good job, then he would be left to get on with it for the duration."

Wilson conceded that the prime minister needs to have some room for manoeuvre in order to cope with unexpected events and to reward talent.

"There has to be a turnover in ministers and people of ability must have the opportunity to rise through the ranks," he said.

And he called for more of his former colleagues to recognise when their time is up.

"It should be regarded as normal for ministers to go voluntarily after doing a decent stint in office, to facilitate turnover," he argued.

No efficient business would run its affairs in the same way, he concluded, and "those businesses and organisations which have to deal with government...want continuity, consistency and the feeling they are being taken seriously".

"Instead, they often get a different minister every time they come to call."