Scotland's Schools Minister issued a “could do better” warning to his own government on education yesterday, saying that the country was in danger of being left behind.

Keith Brown, appointed only two months ago as number two to Fiona Hyslop, the under-fire Education Secretary in Alex Salmond's government, said Scotland's schools were being overtaken. “Unless we raise our game, we will be left behind.”

His remarks during an education debate at Holyrood were seized on by Opposition parties, which interpreted them as a direct criticism of Ms Hyslop. While that was a predictable reaction, Mr Brown can hardly complain since his words were, at the least, unhelpful to Ms Hyslop at a time when she has been attacked by educational interest groups from teaching unions to students.

Mr Brown, responding to a Liberal Democrat-inspired debate, said that for too long, Scotland had rested on its laurels in terms of education.

He admitted international reports showed the country had “not made the progress we might expect”, particularly compared with England. Mr Brown added: “And very worryingly, while they have reached a plateau, those international comparisons also tell us that some of our competitor countries have forged ahead. We are being overtaken and unless we raise our game, we will be left behind.”

Labour claimed that Mr Brown's “attack” would leave Ms Hyslop reeling. Rhona Brankin, the Labour shadow education minister, said: “It's about time someone from the SNP benches realised the mess that Fiona Hyslop is making of education.

“Fiona Hyslop's lack of understanding of schools in Scotland is astonishing. It's now time for her to listen to her own junior minister and up her personal game.”

The Conservatives said Ms Hyslop had been a disaster as Education Secretary and was “not fit for purpose”.

Ms Hyslop has been hit by political turbulence in recent months over a perceived failure to deliver on key SNP manifesto pledges.

Primary class sizes are still well above the 18 limit promised by the SNP in opposition and teacher numbers have fallen by a thousand, instead of rising.

This week, the attacks on Ms Hyslop came from Scottish student leaders, complaining bitterly about the SNP government's failure to deliver on the pledge to abolish student debt and introduce grants in place of loans.

In an open letter to Ms Hyslop, the student leaders told her: “We believe the Scottish government ... has let down students and failed to listen or react to their needs.”

There can be little doubt that the Opposition parties are now targeting Ms Hyslop, believing her to be the weakest member of Mr Salmond's senior team. The Times understands that MSPs from different Opposition parties have even talked about tabling a “no confidence” motion in her, but decided that it is to their political advantage to have her in post.

The Nationalist government dismissed the Opposition taunts last night and argued that with average class sizes in primaries 1 and 2 at a record low and more students in teacher training this year, ministers were in the process of delivering on education commitments over the four-year term.

However, a spokesman refused to be drawn on whether the SNP intended to deliver on abolishing student debt.

The issue of Ms Hyslop's ministerial future also came up at First Minister's Questions, when Tavish Scott, the Liberal Democrat leader, demanded to know from Mr Salmond how long she would remain as Education Secretary.

Mr Scott recalled that Ms Hyslop had said in 2007 that if ministers got education policy right they would “energise an entire generation”.

He said: “Every set of Government statistics shows she has not got it right. How much longer has she got?”

Mr Salmond hit back and said: “You wouldn't have to be a maths student to firstly identify that we have the best teacher pupil ratios in Scottish history.” However, it was noticeable that during his defence of education policy, the First Minister omitted to express his confidence in Ms Hyslop.

Times Recommends

• Please help: maimed children of war want their lives back
• Unlocking the cruellest prison
• Prince Charles named in £81m court battle