In a note in which he set out how he sees Brexit working, analyst Malcolm Barr said JP Morgan's base case was that Scotland will vote for independence, at which point it will institute a new currency.
"Intersecting the UK's EU exit process is likely to be pressure to hold a new referendum on Scottish independence," he wrote.
|Brexit Britain: What you need to know|
"[That will] ultimately generate a vote shortly before the UK leaves the EU in 2019."
Meanwhile, Barr suggested Article 50 will be triggered by the end of the year - unless Conservative MPs act to stop it.
"Constitutional experts argue about whether this is strictly needed or whether the new PM could act unilaterally. In practise we think it inevitable that the new PM would seek a Parliamentary assent given that the referendum is not legally binding. In our view, this is the crucial point wherein Brexit could be stopped, if it is to be blocked.
"Enough Conservative MPs (at this stage, we guess close to 20) would need to defy the leadership to prevent a motion from passing. This would likely generate a confidence vote and possibly a new general election if it occurs. Our base case is that Conservative MPs will fall in behind the leader and implement “the will of the people” as expressed in the referendum."
And he added that it's likely to be 2019 before the UK finally breaks away from the EU, despite the window technically closing in 2018 if we trigger article 50 this year. But Barr reckons negotiation will "focus... on the detail of a set of sectoral arrangements which provide some access to goods sectors beyond World Trade Organisation (WTO) terms.
"Discussion on access to some sectors extending beyond the WTO baseline will likely run beyond the 2020 election, while some sectors will see a reversion to WTO rules for a period while subsequent discussions are promised."
Finally, on the subject of what kind of deal the UK is likely to get with the EU, Barr didn't sound optimistic.
"The UK will ultimately be forced to choose between a “Norway” option (accepting free movement of labour, EU regulations and budget contributions in return for full access to the single market) or an arrangement which has significantly less market access.
"At this point in time, the latter appears more likely."
Countdown to Brexit: JP Morgan's timeline for EU breakaway
After a new Prime Minister is sworn in, the UK will trigger Article 50 before the end of this year. Unless Parliament blocks it - which will require close to 20 MPs to rebel against the leadership.
Negotiations begin on what form the UK's exit from the EU. Talks are likely to focus on the issues relating to exit, rather than those relating to the UK's future relationship with the EU.
The first year of negotiations are likely to be focused on retaining full access to the single market, without the free movement of people.
After lengthy negotiations, the UK may finally break free from the EU by 2019. That's not before a second Scottish independence referendum, after which Scotland may introduce its own currency.