Newspaper headlines: 'The new battle for Britain'
Nicola Sturgeon's proposed timetable for a second independence referendum is the main story for most of the papers.
"May's Brexit plan upstaged as Sturgeon seizes her moment", is the Guardian's headline.
For the Times, it is "Sturgeon ambushes May".
The Daily Mail's message to the Scottish first minister is "hands off our Brexit, Nicola!"
The paper's Scottish edition has a different headline: "SNP's day of betrayal". It says Ms Sturgeon has launched "a new bid to tear Scotland out of the UK".
The Daily Telegraph's headline describes the first minister's plan as "the new battle for Britain".
On a day of high drama, it says, Ms Sturgeon appeared to wrong-foot Number 10 with her announcement.
According to the paper, sources close to Theresa May said she would not allow a referendum until several months after Britain's EU exit.
The Times says allies of Mrs May have made clear that the timing of the proposed vote is "completely unacceptable".
A government source is quoted as saying: "It would be irresponsible to agree to it and we won't."
The Scotsman says the Bute House bombshell was a moment of political high drama.
No one had expected the first minister to announce her intention to request a second referendum quite so soon.
But once jaws had been picked up from the floor, there was a feeling that no matter how dramatic the timing, it was inevitable.
The Herald says Ms Sturgeon has managed to box herself into holding a referendum - with most polls still showing a narrow majority against independence - thanks to her own pronouncements on Brexit.
There is also a feeling that she could not be seen as a nationalist who did not take her chance to hold an independence vote.
Developments in Edinburgh mean coverage of Parliament's approval of the Brexit bill is largely relegated to the inside pages.
However, the Daily Express manages a "hooray" on its front page.
It says Mrs May should now "get on" with triggering the formal process of leaving the EU.
But several papers suggest that Ms Sturgeon's intervention scuppered the prime minister's plans to do so this week.
According to the Telegraph, Whitehall departments had been told to prepare for the big announcement - and ministers had hoped that it would finally shift the agenda away from last week's fumbled Budget.
The Sun says Monday 27 March is now the likely date.
Finally, there is widespread coverage of the Commonwealth Day service at Westminster Abbey.
The Express says the Queen was accompanied by most senior members of the Royal Family - and the prime minister was there too.
But many papers remark on a notable absence.
"So where was William?" asks the Mail.
It earns him a stern rebuke from the Sun, which calls him workshy.
With the Commonwealth taking on an increasing significance in our post-Brexit diplomacy, it says, skipping this blue riband event to hit the slopes sends all the wrong signals.
A Kensington Palace source tells the Express that the Duke and Duchess of Cambridge have attended the service before and will attend it on many occasions in the future.