Nicola Sturgeon has been accused of breaking a promise to put her independence plans “on pause” after she warned only days into 2018 that Tory Brexit plans meant breaking up Britain “must remain an option”.

Attacking what she called the Conservative “horror show” on leaving the EU, the First Minister also claimed there was a “better than evens chance” that a hard Brexit could be stopped.

She predicted a “new spirit of Scottish assertiveness” this year, adding: “We will resist as fiercely as possible the Tory plans for an extreme Brexit, outside the single market and customs union.

“The threat to Scotland’s interests means independence must remain an option. Being torn out of the world’s biggest single market against our democratic will - a market eight times bigger than the UK’s - threatens to do untold damage.”

The Scottish Conservatives said her “naive and arrogant” approach to Brexit had already been punished by the electorate and claimed her view that two democratic votes - the 2014 independence referendum and 2016 Brexit vote - could be overturned would “damage her credibility further”.

Ms Sturgeon was forced to “reset” her timetable for a new independence referendum after a disastrous general election last year which saw the SNP lose 21 seats, including that of Alex Salmond, after pushing for a fresh poll.