ALEX Salmond faced claims he has lost the trust of the people as the row over legal advice on an independent Scotland's European Union membership escalated.

The First Minister agreed to an inquiry into claims he broke ministerial rules by appearing to confirm during a television interview the Government's law officers had been consulted on the issue.

However, he endured furious attacks from Scottish Labour leader Johann Lamont and Tory chief Ruth Davidson during a stormy First Minister's Questions at Holyrood. Ms Lamont told MSPs the First Minister was "straight as a corkscrew" and added: "We can't trust a word Alex Salmond says."

Opposition MSPs claimed his credibility had been fatally undermined by the interview in March when he was asked if he had sought advice from the lord advocate or solicitor general on an independent Scotland's membership of the EU and replied: "We have, yes, in terms of the debate."

Deputy First Minister Nicola Sturgeon revealed on Tuesday the law chiefs had not been consulted at that time, sparking claims Mr Salmond had lied.

At FMQs he dismissed the claims and maintained he had been speaking in general terms about Government documents on EU membership which were "underpinned" by legal advice. He added: "Of course an independent Scotland would be a member of the European Union."

The inquiry – the sixth Mr Salmond has faced into allegations of breaching the Government's strict ministerial code of conduct since becoming First Minister – will be headed by Sir David Bell, the vice-chancellor of Reading University and a former senior Whitehall mandarin. Two former lords advocate, Dame Elish Angiolini and Lord Fraser of Carmyllie, will also take part. Mr Salmond said: "The findings of the independent adviser will be made public. I will accept them and I hope that all members of this chamber will do likewise."

However, Labour MEP Catherine Stihler – who fought a 17-month Freedom of Information battle over the legal advice until ministers dropped court action blocking it this week – said: "This is a smokescreen by Alex Salmond.

"My question wasn't just about the ministerial code. I wanted to know why he went to court at the taxpayers' expense rather than answer simple questions. Appearing before his own hand-picked court will do nothing to regain the trust he has lost."

Other opposition politicians also claimed the row had shattered trust in the First Minister.

Ms Lamont said: "Alex Salmond's refusal to tell the truth is now an embarrassment to Scotland."

Ms Davidson said: "Alex Salmond has lost the trust of the people of Scotland and nothing he said helped to clear up this shambles."

The Scottish Government has claimed in three key documents that an independent country would continue as a member of the EU on the same terms as the UK. But the President of the EC, Jose Manuel Barroso, and Spain's Foreign Minister Jose Garcia-Margallo have both said Scotland would have to "join the queue and ask to be admitted," negotiating fresh terms.

The First Minister's chief spin doctor yesterday insisted the documents were "underpinned by legal advice".

Meanwhile, Mr Salmond was mocked by MPs yesterday in the House of Commons. Tom Harris, the Shadow Environment Minister, asked Andrew Lansley, the Leader of the House, if he could give a helping hand to Mr Salmond who "recently has mislaid some really important legal advice about the future of an independent Scotland within the EU?"

l An SNP politician has called for two former colleagues to leave parliament after resigning from the party in protest at the Nato membership U-turn.

Christine Grahame said Jean Urquhart and John Finnie should step down as both were elected on the regional list, meaning they took their seats to represent support for the SNP, not as individuals.