NICOLA Sturgeon has said there is "no doubt at all" that lax UK border controls contributed to the rise of the Delta variant.

The First Minister said the failure to introduce tougher rules was "deeply frustrating" and the country is now "paying a price" for it.

It came as she signalled a delay to Scotland's lockdown easing, warning it is "unlikely that any part of the country will move down a level from June 28".

It had been hoped the whole of Scotland would move to Level 0 from that date.

Instead, Ms Sturgeon said it is likely ministers "will opt to maintain restrictions for a further three weeks from June 28 and use that time to vaccinate - with both doses - as many more people as possible".

Speaking in Holyrood, the First Minister said the the faster-transmitting Delta variant of the virus, first identified in India, is now common across Scotland.

She said: "I have spoken in the past...about my intense frustration at the lack of more robust controls around the UK border more generally. 

"I think we are paying a price for that right now, if I can be very blunt about it."

Responding to questions from MSPs, she said: "There is no doubt, and I don't think I'm the only person that will say this, that the lack of very robust border controls in recent months has, I think, been a factor in the situation we're dealing with right now, and that is deeply frustrating."

She added: "If we cast our minds back to mid-February, the Scottish Government decided to insist on mandatory managed quarantine for all direct arrivals into Scotland, regardless of what country they came from – so that would have included India. 

"At that time, despite our pleading, the UK Government only insisted on managed quarantine for red list countries, and it took until the latter part of April to put India on the red list."

She continued: "We pleaded with the UK Government to put common provisions in place across the UK, but we also pleaded with them to introduce a situation where people coming into an English airport but intending to go to Scotland would be made to quarantine at the point of arrival.

"[Cabinet Office minister] Michael Gove, I think, wrote to the Transport Secretary back in February refusing point-blank to do that."

Ms Sturgeon said: "There is no doubt at all that too lax border controls around the whole of the UK have played a part in where we are right now."

Scottish Greens co-leader Lorna Slater said restrictions on international travel must remain in place to allow the rest of the economy to return to something like normality.

She said: "The recent exponential growth of Covid cases in Scotland is cause for concern, and there is a risk of yet more people dying and suffering from long Covid, before the vaccine roll-out can be completed.

“The Scottish Greens have supported a cautious approach throughout the pandemic, and I welcome the decision to delay lifting restrictions today.

“The travel industry are already advertising and selling holiday, actively encouraging people to travel, even to amber list countries, for non-essential travel, even to amber list countries, for non-essential reasons, not just for family reunions, despite the risk.

"The Scottish Government must adopt a much firmer line on non-essential international travel, particularly while other businesses which pose a much lower risk are still prevented from operating normally.

“The First Minister must accept that if we want to end restrictions, in a safe, and permanent way then non-essential international leisure travel will have to be the last thing to return to normal.”

Ms Sturgeon said international travel "is likely to be one of the last things to go back completely to normal".