SNP MSPs have been accused of preventing a legal expert from criticising the Scottish Government's white paper for independence at a Holyrood committee.

Adam Tomkins, Glasgow University chair of public law, was interrupted by SNP MSP Willie Coffey while highlighting "inaccurate" information in the white paper, and was cut off by SNP MSP Christina McKelvie.

Ms McKelvie, the committee's convener, said she is permitted to cut off evidence "if it's becoming contentious".

Labour MSPs Patricia Ferguson and Alex Rowley loudly protested, along with Conservative MSP Jamie McGrigor, and when Mr Tomkins was allowed to return to his point 25 minutes later he said he felt as if he had been "told off".

Mr Tomkins said: "In the white paper it is stated that Scotland 'would be entitled to a fair share of the UK's extensive overseas properties allowing us to use existing premises for some overseas posts'. This assertion has no basis in law.

"It's unfortunate that the independence white paper, the most important document published in the lifetime of the Scottish Government, proceeds on an inaccurate footing as a matter of international law. Either legal advice wasn't taken or it wasn't understood."

Ms McKelvie challenged Mr Tomkins with evidence from Kings College politics lecturer Dr Andrew Blick, who said "there is a legal case for saying that the UK is dissolved and that there are two successor states", and former US ambassador for war crimes Dr David Scheffer, who said "the break-up should be viewed as two successor states of equal legitimacy".

Mr Tomkins said Dr Blick "is not a lawyer" and was "profoundly wrong" while Dr Scheffer was "mistaken in international law".

Mr Coffey said: "I'm a wee bit disappointed by the tone of some of Professor Tomkins' contributions here.

"It's almost as if there's going to be a great big bunfight, a battle, arguments, disagreements and aggression after independence.

"If you're right that in international law that the UK 'keeps everything' and we start from scratch, I would suggest that's not how it will play out."

Mr Tomkins said: "I have not said that that means that the UK 'takes everything'. On the contrary, I have said..."

Mr Coffey began shouting across the room and both were silenced by Ms McKelvie.

Mr Rowley shouted: "I think the witness should continue giving evidence.

"You may not like the evidence but you can't just cut the evidence off because you don't like the evidence they're giving, for goodness sake."

Ms McKelvie said: "I can if it's becoming contentious. I'm sorry Alex, I'm the convener and I can decide."

Ms Ferguson said: "I have no problem with any of the evidence that has been given by any of the witnesses this morning.

"But even if I did, I think I would hear it respectfully and consider it when I come to my deliberations when the committee makes its report.

"I'm really worried that we're in danger of not doing that today and I really do think that we need to hear what Professor Tomkins has to say and then perhaps move on. I think interrupting a witness is not appropriate."

Ms McKelvie said: "I interrupted both of them."

Mr Rowley said: "With the greatest respect, Willie Coffey was interrupting the witness and that's what you should have stopped, not the evidence."

Mr McGrigor said: "I want to make a protest that on this occasion the convener stopped a witness in mid-stream from completing his evidence and I'm glad that this in the public domain today."

Ms McKelvie said: "We obviously have nothing to hide in this committee, but there was a dual exchange across the table and that's what I wanted to stop, and then when we came to the end of our evidence that was why I wanted Professor Tomkins to come back in and finish what he had to say."