BBC executives have rapped Andrew Neil after claiming that one in five Scottish children leaves primary school "functionally illiterate".

The Sunday Politics presenter made the assertion while tackling former First Minister Alex Salmond over the SNP's record on education on his show.

Complaints were made to the BBC as Mr Neil, who is no longer the show's host, questioned Mr Salmond over the funding of schools in Scotland.

In the show broadcast in April, Mr Neil, reading from, what appears to be a prepared script, asks Mr Salmond: "If it was so well funded, and if services have been so well protected, why after a decade of SNP rule do one in five Scots pupils leave primary school functionally illiterate?"

HeraldScotland:

Mr Salmond responded saying: "Well, there are challenges in education, Andrew, but you have to take these things in the round. Nicola Sturgeon has made it a top priority to address these challenges. But let's take another statistic, 93 per cent of Scottish kids are now emerging from school to positive destinations, that means to further education, apprenticeships or into work...

Mr Neil interrupted: "Why are one in five functionally illiterate?"

HeraldScotland:

Mr Salmon responded: "Well, you argue one statistic, I'm arguing in the round Scottish education is putting in some substantially good performances like the 93 per cent, a record figure, who are going on to positive destinations.

"You can't have a failing education system if you've got that 93 per cent and, incidentally, a record low youth unemployment in Scotland...the second lowest unemployment rate in Europe. These pupils are being prepeared by the Scottish education system. An investigation was launched following a complaint that there was no basis for the literacy claim and the BBC’s complaint unit agreed.

The BBC executive complaints unit said the figure had originally been put forward by a spokesperson for the Scottish Conservatives as being based on the 2009 Scottish Survey for Literacy and Numeracy.

But the unit said the survey "contained no reference to 'functional illiteracy', and added that there was"no data which would have justified the claim in question".

The unit said: "The Sunday Politics team has been reminded of the need to establish the evidential basis of claims that are quoted in its questions."

In May, The Scottish Survey of Literacy and Numeracy found that less than half of Scotland's 13 and 14-year-olds are now performing well in writing.

P4 and P7 pupils also saw a drop in writing performance.

The reading ability of P4, P7 and S2 pupils remains broadly similar to 2014 - but lower than 2012.

Scottish Education Secretary John Swinney then accepted that the figures were "simply not good enough" and showed that education reforms were now "imperative".

Mr Swinney added: "If anyone looking at these literacy results thinks nothing more needs to change in Scottish education, then they are mistaken."