BORIS Johnson's Brexit deal could cost Scotland around £9 billion over the next decade and hit jobs and the economy "at the worst possible time", the Scottish Government has warned.

Constitution Secretary Michael Russell said extra costs could make Scottish businesses uncompetitive in key markets such as manufacturing, agriculture and food and drink.

The 27 EU states are expected to formally back the post-Brexit trade deal within days after an agreement was confirmed on Christmas Eve, four a half years after 2016's referendum.

Ambassadors from the member states were being briefed on the contents of the deal on Christmas Day by Michel Barnier, who led Brussels' negotiating team in the talks with the UK.

MPs and peers will be called back to Westminster on December 30 to vote on the deal, but MEPs are not expected to approve it until the new year, meaning it will have to apply provisionally until they give it the green light.

The draft treaty and associated Brexit agreements stretch to 1,246 pages of complex legal text.

SNP ministers said Scotland is being removed from a market worth £16bn in exports to Scottish companies, and which by population is seven times the size of the UK, as well as the Customs Union.

They said lamb and beef exports will be hard hit by the extra costs of exporting to the EU.

Businesses trying to access UK and EU markets will also face additional bureaucracy and costs, they said. For example, the seafood sector will require new certificates and changes to business practices to continue to export to the EU.

Elsewhere, the Scottish Government said justice and security cooperation will be "seriously impacted", with Police Scotland and the Crown Office having to use slower and less effective tools in the fight against crime.

It said reduced EU migration will have a significant negative impact, increasing shortages in key areas such as health and social care.

And it insisted the Scottish fishing industry "will see only a fraction" of the additional quota promised and the compensation arrangements agreed if the UK Government restricts access to UK waters.

Scottish students will also no longer be able to participate in Erasmus.

The Scottish Government said its modelling estimates that "a deal of the type that appears to have been agreed" could cut Scotland’s GDP by around 6.1 per cent – £9bn in 2016 cash terms – by 2030 compared to EU membership.

Mr Russell said: “A no deal outcome has thankfully been avoided but in the midst of a pandemic and economic recession Scotland is now being forced to cope with a hard Brexit in less than one week’s time.

“Leaving the European Single Market and Customs Union would be damaging at any time but in the middle of the current crisis it is unforgivable and completely unnecessary.

“We are doing everything we can to mitigate against the consequences of the UK Government’s actions.

“Measures are being taken to protect trade and critical supply chains, to reduce the risks of disruption of goods and people crossing borders and to provide Scottish businesses with the vital advice and information they need to continue operating effectively after 31 December.

“We are also working with UK administrations to ensure patients get the medicines and medical supplies needed and we are also confident that the flow of vaccines will be protected.

“Throughout this entire Brexit process the Scottish Government has sought to engage constructively with the UK Government on preparedness and we will continue, as we always have done, to advocate for the interests of Scottish businesses and of Scottish people whenever possible, but we simply cannot avert every negative outcome.

“People in Scotland voted overwhelmingly to remain in the EU and have the right to determine their own future rather than face the long-term damage of a hard Brexit.

“Scotland is at heart a European nation, and shares it values. The UK Government has ignored our calls for a continuing close relationship with the EU and it is clearer than ever that the only way to regain the benefits of EU membership is for Scotland to become an independent country.”

Mr Johnson hailed the deal struck with the EU as a "new beginning" for Britain that resolves the European question that has "bedevilled" British politics for generations.

But fishing leaders claimed he had sacrificed the industry to secure a trade agreement, while Labour leader Sir Keir Starmer branded the accord "thin" - although his party will back it in next week's Commons vote because the alternative would be a "devastating" no-deal scenario.

Late haggling meant the deal was not concluded until Christmas Eve, days before current trading arrangements expire at the end of December.

Mr Johnson said the document "will be the basis of a happy and successful and stable partnership with our friends in the EU for years to come".

The Prime Minister has claimed the deal meets the goals set out during the 2016 campaign to "take back control".

He said it covers trade worth around £660bn and means goods and components can be sold without tariffs and quotas in the EU market. 

Meanwhile, the share of fish in British waters that the UK can catch will rise from around half now to two-thirds by the end of the five-and-a-half-year transition, he said. 

Allegations of unfair competition will be judged by an independent third-party arbitration panel with the possibility of a "proportionate" response.