Theresa May has failed to guarantee the UK will leave the Common Fisheries Policy (CFP) by the December 2020 deadline.
On a visit to Aberdeen, the Prime Minister stopped short of giving a firm assurance that the fishing industry’s demands to quit the controversial European Union arrangement by the end of next year would be met.
Mrs May said, unlike the SNP, the Scottish Conservatives would “guarantee” the UK left the CFP.
However, on the deadline itself, she would only say that the UK Government was “working” towards it.
“The timetable the Withdrawal Agreement has within it is still for that end of the implementation period in December 2020 and obviously, we will still be working to that,” the Prime Minister said.
When asked for a second time if she could guarantee the December 2020 deadline would be met, she replied: “We have to leave the European Union first, so I want to ensure that across parliament we can get the majority that enables us to deliver Brexit.”
The establishment of the UK as an independent coastal state by the end of next year has been a “red line” issue for Scottish Tory leader Ruth Davidson and Scottish Secretary David Mundell as well as the Scottish fishing industry.
The extension of the Brexit timetable has led to fears within the industry that the delay could threaten its ambition to take control over UK waters.
Bertie Armstrong of the Scottish Fishermen’s Federation said: “The industry is solidly behind the date of December 2020, which was agreed. Despite the delays to the start of the implementation period, there has to be no change to that.
“Attempts are being made by local MPs to place that date in primary legislation.
“The sea of opportunity lies beyond the end of the implementation period and until then we are trapped in this unworkable and unfair arrangement.”
Mrs May was speaking after her keynote speech to the Scottish Conservative Conference at the Aberdeen Exhibition and Conference Centre.
The Prime Minister arrived in the Granite City having suffered the humiliation of losing more than 1,000 council seats in the English local elections, a result which raised yet more questions over her leadership and handling of Brexit.
She used her speech to attack Nicola Sturgeon and her plans for independence, claiming the SNP leader was not interested in working with her to deliver a good Brexit deal.
“She (Ms Sturgeon) saw Brexit as an opportunity to further her party’s obsession with one thing and one thing only – independence,” Mrs May said.
The Conservatives’ determination to thwart Ms Sturgeon’s plans for a second independence referendum was a theme throughout the opening day of conference.
In his speech, Scottish Secretary David Mundell said the UK Government would say “no” to any demands for a Section 30 Order, a second Edinburgh Agreement or a legal referendum.
Today the Scottish Tory leader Ruth Davidson was to mark her return to front-line politics after six months of maternity leave pledging “no more constitutional games and no more referenda” if she becomes first minister.
In her speech, Ms Davidson said she will declare Scotland has had enough constitutional politics “to last a lifetime” and say the SNP will be “arguing that they can’t make things better without putting us all through another referendum first”.
She will add: “I have a more positive view of Scotland’s future.
“I reject their mantra that says we have to have a break up before we can possibly hope to prosper. I don’t see Scotland as subjugated, put upon or as held back.”