Private school students are three times more likely to appeal the results of their exams than children at a local authority school, new figures have revealed.

Statistics from the Scottish Qualifications Authority (SQA) showed that in 2015 independent schools appealed 6% of exam results compared to 2.1% of results that were appealed by council-run secondaries.

The figures, which were revealed in evidence from the SQA to MSPs on Holyrood's Education Committee, promoted fresh calls for appeal charges to be scrapped.

The fees, introduced by the Scottish Government in 2014, are only applied if no change is made to the exam grade.

However, if the appeal is unsuccessful, schools are charged £10 for a clerical check to see if marks were added up correctly and £29.75 for a marking review, with this rising to £39.75 if it is done on a priority basis.

With school budgets coming under increasing pressure, it is feared the charges could deter some local authority schools from putting forward appeals.

In 2013 local authority schools submitted 62,486 appeals, but the following year the total dropped to 7,056 before rising again in 2015 to 9,584.

Labour education spokesman Iain Gray criticised the Scottish Government, saying: "Kezia Dugdale and I have raised this with SNP ministers again and again, but it seems that they could not care less about this unfairness in the system.

"They talk the talk on equity, so they should back a fair education system by committing to scrap these unfair fees, and level the playing field for every pupil."

With the 2016 exam results published earlier this week, Mr Gray said: "Pupils across Scotland will be considering this weekend whether to appeal grades they received on Tuesday.

"An exam appeal decision can be the deciding factor between a pupil getting to college or university, with all the opportunities that may bring. Money shouldn't come into it.

"The figures clearly show that the SNP's introduction of exam appeal fees has put pupils from state schools at a disadvantage compared to those educated privately. That is just not fair."

A Scottish Government spokeswoman said: "No young person is at a disadvantage through the results service in Scotland. Only schools and colleges can make requests to SQA's results services.

"Whether the pupil is from a local authority or independent school, a review can only be requested if the school has a legitimate query about a candidate's results.

"As with all SQA charges, local authorities meet the costs of requests by public sector schools to use this service. "National guidance from education directors makes clear that no young person should be denied access to this service on the grounds of cost."

This year's results showed students passed a total of 152,701 Highers in 2016, with an attainment rate of 77.2%, down on the 156,000 passes in 2015 but still the second highest number on record.