Former Swedish PM Carl Bildt warns on Brexit trade deal
The former prime minister of Sweden, Carl Bildt, has predicted that making Brexit happen will take the UK longer than it expects.
Theresa May has proposed a period of "around two years", after the UK leaves the EU in March 2019, during which our long-term relationship would be finalised.
But in a BBC Scotland interview, Mr Bildt said it would "almost certainly" take longer because of the complexity involved.
EU leaders are gathering in Brussels where they are expected to agree that Brexit talks can now move into a second phase.
This will allow negotiation on transition arrangements and the broad shape of future UK-EU relations, including trade and security.
Brexit secretary David Davis has said the UK is seeking a more extensive free trade agreement than the EU-Canada deal.
He has called for a "Canada plus plus plus" arrangement allowing free trade in services as well as goods.
In his BBC interview, Mr Bildt said: "I think services is going to be very complicated.
"And I think there will be the difficulty of going substantially further with the UK than the EU has gone with its other partners."
Carl Bildt was Sweden's prime minister minister from 1991-1994, and the country's foreign minister for eight years until 2014.
He believes negotiating and implementing a deal may take longer than the UK thinks.
"There are quite a number of other things that are being negotiated by the European Union at the moment," he added.
"Almost certainly it's going to take more than the two years that are discussed as the transition period."
During the transition, the UK would be outside the EU but trading with it on similar terms by remaining closely aligned with the European single market and customs union.
If the transition lasted much longer than two years, it could make the terms of Brexit an issue in the 2022 general election.
The UK government wants to avoid that.
It became possible for Brexit talks to move towards a second phase after the UK and the EU struck a deal last week on so-called "divorce" issues.
These include citizens' rights, the Irish border and the financial settlement.
This agreement now needs to be made legally binding.
Negotiators have until October next year to agree the transition deal and the framework for future relations, to allow time for that to be approved by the European Parliament before Brexit day.
EU council president Donald Tusk has described the timescale as a "furious race against time".
The Scottish government has argued for continued membership of the single market and customs union.
Mr Bildt has previously said that "makes eminent economic sense".
However, he does not think there could be a special deal to allow Scotland to stay in if the rest of the UK is coming out.
"I think that's too complicated and the European Union is in the business of having relationships with other states," he said.
"As long as Scotland remains part of the United Kingdom, I think it's very difficult to see that it will not be part of the overall solution for the United Kingdom."
First Minister Nicola Sturgeon has said she would accept Brexit if the UK as a whole stays in the single market, or negotiates for Scotland to do so.
The UK government has rejected that approach.
Ms Sturgeon is to review the option of holding a second referendum on independence once the terms of Brexit are clearer.
She put on hold plans for a vote between autumn 2018 and spring 2019 after the SNP lost ground in the UK general election.