Nicola Sturgeon will reiterate her call for the UK to remain part of the single market and customs union when she addresses an economic forum later.
Scotland’s First Minister will tell the event in Dundee that Brexit in any form is likely to reduce economic growth.
She is expected to tell delegates that leaving the single market will do “immense damage” to jobs and living standards in Scotland.
Ms Sturgeon will say: “The UK Government’s refusal to even consider the Scottish Government’s detailed plan to keep Scotland in the single market, while accepting a differentiated solution for Northern Ireland, which we support, potentially puts Scotland at a competitive disadvantage.
“But, perhaps worst of all, it leaves everybody completely uncertain about the shape of our long-term relationship with the EU.
“The seven-page political declaration on the future contains little more than vague aspirations and platitudes.
“But while we can expect more pages forthcoming on some aspects of the future relationship, there will be no concrete reassurances.”
The Scottish government’s National Economic Forum is a regular event attended by ministers and senior figures from business, the public sector and trade unions to discuss how best to grow Scotland’s economy.
She will say: “Put bluntly, long-term economic uncertainty is hard-wired into the Prime Minister’s withdrawal deal.
“If the UK Government insists on leaving the EU, then it should remain in the single market and customs union.
“That is the solution which respects the outcome of the referendum, mitigates the worst economic consequences of Brexit and largely resolves the Irish border issue.
“If Brexit goes ahead, in any form, it is likely to reduce economic growth.
“But that doesn’t devalue our wider efforts to support business, in fact it makes those efforts all the more important.”
On Sunday Ms Sturgeon said SNP MPs will vote against the Prime Minister’s EU withdrawal plan.
She told the BBC’s Andrew Marr Show the draft agreement lacked clarity on the UK’s future relationship with the EU, and the Commons was going to be asked to endorse a “blindfold Brexit”.
Outlining what she said were potential alternatives, Ms Sturgeon said: “If the House of Commons says we want to go down the road of single market and customs union membership, we want more time to take this back to the people of the UK in another vote, we need an extension of Article 50, if there is a clear change of direction, then I believe the EU 27 would be prepared to look at that.
“But that means those who don’t want this deal coming together.
“Those who don’t think the Prime Minister’s deal is the right way to go have now a responsibility to come together and coalesce around an alternative.
“I will seek to have discussions this week with other parties to get us into that position.”
She also said she was keen to talk to Labour leader Jeremy Corbyn “and whoever else” in the House of Commons when she visits London in the coming days.