DIVISIONS between Scottish councils could lead to a "creeping privatisation" of education, a trade union leader has warned.

The claim comes after four councils quit the national body which represents the country's 32 local authorities - the Convention of Scottish Local Authorities (Cosla).

Teachers' pay and conditions are negotiated through Cosla and the body also agrees policy objectives with the Scottish Government such as maintaining teacher numbers or delivering free school meals.

The four local authorities who left to set up a new organisation called the Scottish Local Government Partnership (SLGP) have pledged to continue to be part of the country's collective bargaining arrangements.

However, Seamus Searson, the new general secretary of the Scottish Secondary Teachers' Association (SSTA), said he was concerned moves by Aberdeen, Glasgow, Renfrewshire and South Lanarkshire to leave Cosla because of political differences could damage education.

Speaking on the eve of the union's annual congress, Mr Searson said: "There is a need for a sustainable education system to support schools with local authorities entrusted and responsible for schools.

"I fear that the recent decision by four local authorities to leave Cosla could open the door to outside agencies or trusts being given responsibility for schools - these bodies would not be under local democratic control and could threaten the whole education system in Scotland.

"I urge the four authorities not to play politics with education and return to Cosla and maintain a national education system with national pay and conditions."

In a wide-ranging speech, Mr Searson called on the Scottish Government and councils to recognise recent cuts in teachers' pay, adding: "This must mean a substantial increase in pay in the coming years to retain and attract teachers."

He also raised concerns about whether one of the new qualifications which replaced Standard Grade was being properly run.

National 4 qualifications have no external exams and some teachers have suggested they are under pressure to pass all pupils.

Mr Searson said: "I do have concerns about National 4. If we have qualification they must of value, but we have heard of undue pressure being applied in some schools to achieve National 4 for all young people in their classes.

"Should the system demand all students reach National 4 then the qualification and all the effort would be to no avail."

Meanwhile, the SSTA's acting president Elaine Henderson is expected to highlight long-standing concerns over a shortage of supply teachers.

She will tell the congress in Crieff: "Schools are unable to function without an experienced and professional group of teachers.

"The changes to supply teacher pay has led to the current shortages in supply across the country and we need to work with Cosla and the Scottish Government to seek a long-term solution.

"The supply teacher should be a valued member of the school community and not just the poor relation for whom nobody wants to take responsibility. Supply teachers have an entitlement to proper contracts of employment and salary that reflects the importance of the role."