Nicola Sturgeon stated that there would be a widespread sense of relief after Boris Johnson's resignation.
After losing support from his MPs and ministers, the prime minister has resigned as party leader.
Outside Number 10, Johnson stated that he would remain as prime minister until his successor is chosen.
However, Scotland's first minister was skeptical about whether this approach is sustainable.
Ms Sturgeon stated to BBC Scotland that the chaos and lack of integrity which has characterised Boris Johnson’s premiership has descended into complete absurdity in the past few days, at a time when many people across the UK are facing very real problems.
"First and foremost, there will be an overwhelming, very widespread feeling of relief today that Boris Johnson is ending his time as prime minister. This should not have happened in the first instance.
She stated that it was unbelievable to suggest that Mr Johnson would remain as prime minister for three to four more months. Douglas Ross, her political opponent from the Scottish Conservative Party, shared this view.
Ms Sturgeon said: "It's just an unsustainable proposition for him to continue to live in Number 10." Boris Johnson is not a person that could be considered capable of acting as a caretaker prime minster.
"He will do anything he wants and cause more chaos than he's already caused."
She stated that the Westminster government's "democratic deficit" would not be corrected by a change in PM.
Ms. Sturgeon felt that the Westminster system was not in Scotland's best interest and added, "Scotland requires a permanent alternative than Westminster which is why independence is so important."
Ms. Sturgeon stated that, despite her deep differences with Mr Johnson, she was able to see that the leadership role is difficult and brings with it many strains and stresses. She wished Mr Johnson and the family well.
Johnson had promised to "keep going" despite the wave of resignations, despite senior Cabinet members, including Nadhim Zahawi as chancellor, asking him to resign to leave "with dignity."
Thursday morning it was revealed that Johnson had decided to resign.
He said, "It is now the will of parliamentary Conservative Party that there should a new leader for that party and therefore a prime minister."
"And Sir Graham Brady, our chairman of backbench MPs, has agreed that the selection process for the new leader should start now, and that the timeline will be announced next week.
"And today, I have appointed a Cabinet to serve, and I will until a new leader takes place."
British citizens were addressed by Johnson, who said: "I want to tell you how sorry I am to have to give up the best job, but they're the breaks."
Scottish Tory Mr Ross stated that the decision to resign was right.
He believed that it would be very difficult for the prime minister for him to continue in this role for "several months more".
After Mr Johnson had indicated that he would resign but before he made the statement outside 10 Downing Street, Mr Ross spoke.
BBC Scotland was informed by the leader of the Scottish party: "It is very difficult for PM to continue for many more months due to what has happened with resignations from his Cabinet saying they can't support him as Ministers."
"We have many vacancies that I don't think even an interim PM can fill. The best solution is to have an interim PM, as we had during the Covid pandemic. Dominic Raab was there just a few weeks ago and it was a great help.
Anas Sarwar, leader of Scottish Labour, said that Mr Johnson's statement was "a sigh relief that Boris Johnson has gone".
He said, "This party is rotten to its core, which allowed a cheat and a charlatan to become the prime Minister of this country - they inflicted their carnage upon this country for many years."
Patrick Harvie, co-leader of the Scottish Greens, said that it was a relief to see Boris Johnson's "disastrous tenure" as prime minister come to an end.
He stated that Johnson was not fit for high office. Johnson's lies, lawbreaking and incompetence were all facilitated by the Conservative Party.
The Scottish Liberal Democrats tweeted "It has always seemed clear that Boris Johnson was unfit to lead this country." The Conservatives won't be forgiven for allowing him to continue his rise.
"Lifelong conservative voters are tired of being taken for granted. Trust in the Conservatives is gone, and it won’t be returning."
It is possible to wonder if Nicola Sturgeon was in secret sad to see Boris Johnson leave.
The SNP loves to campaign against him, after all. He is a prominent and regular feature in their campaign ads. This makes him a stranger to the Scottish Tories.
Is there a small part of the first minister who feels she has missed the opportunity to stand up against Johnson in an independence referendum vote?
She said no, and the escalating chaos in Westminster will only strengthen the case for independence.
Ms Sturgeon claims that any Tory prime Minister is just as bad as any other, and she would gladly accept any candidate for the job.
However, it is not clear when she will be able to vote in a referendum or general election.
The pieces are up in the air with Johnson's departure, and other leaders are still waiting to see their fate.
This could be the moment when poltics is reset. It's difficult to plan or predict what will happen next.
