A SECOND referendum on Scottish independence came a step closer yesterday, as the Prime Minister told Nicola Sturgeon the terms of Brexit would be known before the spring of 2019.

The First Minister seemed almost taken aback at how quickly Theresa May offered up assurances that people in Britain would know the “exit terms, the divorce deal, and the detail of the comprehensive free trade agreement – in other words the future relationship between the UK and the EU” within the next two years.

May has previously said that “now is not the time” for a referendum, with other senior Tories saying it would be unfair for voters to have to go to the polls before there was clarity on what Brexit would actually look like.

Sturgeon said the clarification yesterday afternoon meant there was now no longer a “rational” argument against a vote on independence between Autumn 2018 and Spring 2019, as initially suggested by the SNP leader two weeks ago.

Sturgeon and the Prime Minister met in Glasgow yesterday as part of the Tory leader’s tour of the UK ahead of her triggering Article 50, the formal process for Brexit.

Speaking to reporters afterwards, the First Minister said: “When I put it to her that what she was suggesting was that in a period of around 18 months from now to two years from now, the terms of the future relationship between the UK and the EU would be clear, she said yes, that is what she was saying.” Sturgeon insisted she been “at pains” to make sure she had not misunderstood May.

She added: “I think it makes it very difficult for the PM to maintain a rationale opposition to a referendum in the timescale that I have set out.

“I think she’s got a perfectly rational opposition to a referendum now, which is why I’m not proposing it. But I think based on the discussion today I would struggle to see what her rational opposition to it would be in the timescale we’ve been talking about.”

Sturgeon insisted the Prime Minister was under no illusion as “to the significance of me pressing her on that point.”

Two weeks ago May rejected calls for a second referendum, saying that “now was not the time” and that “all our energies should be focused on our negotiations with the European Union about our future relationship".

Ahead of the meeting, May told reporters her position was “very simple” and had not changed since she first rejected Sturgeon’s request.

“It is that now is not the time to be talking about a second independence referendum and that’s for a couple of reasons.

‘’First of all, now is the point when we are triggering Article 50, we’re starting negotiations for leaving the European Union. Now is the time when we should be pulling together, not hanging apart. Pulling together to make sure we get the best possible deal for the whole of the UK.

‘’Also I think it would be unfair on the people of Scotland to ask them to make a significant decision until all the facts were known, at a point where nobody knows what the situation is going to be.”

That statement was followed up by a press conference with Secretary of State for Scotland David Mundell and Scottish Tory leader Ruth Davidson.

There Mundell had said it would be wrong to get “bogged down in arbitrary dates or somehow constructing a shadow referendum campaign that could go on for years.”

The request for a referendum would, he said, be declined as it was “asking people to choose Scotland’s constitutional future at a time when people in Scotland could not make a fair assessment of alternatives.”

Davidson argued that “the people of Scotland should not be subjected to another referendum until we can clearly see what the two options are ahead of them on both sides of the argument”.

Yesterday, according to Sturgeon, the Prime Minister appeared to suggest she agreed with the First Minister that there could be an informed choice if the vote was “held between the autumn of 2018 and the spring of the following year.”

However, a source at Number 10 disputed Sturgeon’s claims. telling the BBC’s Laura Kuenssburg it was “for the birds” to think a deal would be all done in 18 months, and that voters would only know bare bones. “They need to know how it operates in the real world” before any future referendum, the source said.

Sturgeon then tweeted back: “PM v clear to me in meeting that she intended terms of Brexit – exit & future deal – to be clear before UK leaves & in time for ratification”

The Prime Minister’s visit came just 48 hours before she plans to trigger Article 50, the formal process for leaving Europe, and right before today’s rescheduled Holyrood vote and Section 30 debate on a second referendum.

Last Wednesday’s session in Holyrood was suspended after the terrorist attack in Westminster that left five dead.

The First Minister is expected to reopen the debate, updating MSPs on the details of her discussion with the Prime Minister.

The meeting between the two leaders in the city’s Crowne Plaza hotel – Number 10 had declined the Scottish Government’s offer of a space in its Glasgow offices – came after the Prime Minister delivered a speech to Department for International Development civil servants in East Kilbride.

May also met the Chief Constable of Police Scotland, Phil Gormley, to talk about security and terrorism.

But it was the constitution that dominated her time north of the Border.

Despite hints in the weekend newspapers about new powers, none were offered by May. Sturgeon said: “I think it’s fair to say there is still no real guarantee that powers repatriated to Brussels in areas that are currently devolved will not end up being centralised at Westminster, and there was no real willingness to talk about powers beyond that – for example powers over employment law or immigration.”

She added: “The expectation that there may have been an offer that we couldn’t refuse that was going to be put on the table didn’t quite materialise”

When asked if she knew what the point of May’s visit to Scotland was, if not to offer extra powers, Sturgeon replied: “I think you’d probably have to ask the Prime Minister that. I was happy to meet.”