A top civil servant, Philip Rycroft, is being shuffled into the Brexit department to scrutinise divorce talks and ensure efforts to deter Scottish independence are not undermined.
He will look at which powers can be taken back from Brussels and devolved to Holyrood, to sweeten the pill of Scotland, which voted strongly to Remain, leaving the EU.
Meanwhile Whitehall ministers are scheduling more meetings north of the border in a bid to keep Scottish counterparts on side, the Telegraph reported.
The move to appease Scotland comes after First Minister Nicola Sturgeon stunned Westminster by calling for a second referendum on independence by 2019.
She called a surprise press conference at short notice on March 13, where she announced she wanted to begin the process towards another ballot before Brexit talks have concluded.
The announcement caught Number 10 by surprise – and left Prime Minister Theresa May visibly angry during a TV interview.
“The tunnel vision the SNP have shown today is deeply regrettable,” Mrs May said.
“It's set Scotland on a course for more uncertainty and division, creating huge uncertainty.”
Mr Rycroft already heads up the cabinet office’s UK Governance Group, with responsibility for constitutional and devolution issues.
Whitehall is plotting to end Nicola Sturgeon's dream of an independent Scotland
He has now been appointed the Brexit department’s second permanent secretary and will study the implications of Brexit decisions on Scottish attitudes towards the Union.
A source told the Telegraph: “As he [Mr Rycroft] will still be responsible for devolution and the Union, it will put keeping the UK together closer to the task of managing the UK’s exit from the EU.
“Both need to be priorities for the present government.”
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Scotland voted to stay in the UK in the last referendum by 55 per cent to 45 per cent.
But the EU referendum moved the goalposts, taking Scotland out of the EU despite Scots voting 62 per cent to 38 per cent in favour of Remain.
There had been an expectation Brexit would shift opinion in Scotland back towards independence – and Ms Sturgeon has gambled on that being the case.
But figures from polling website What Scotland Thinks suggests the outcome of a second referendum, if held now, would be much the same as the last – despite the shock of Brexit.