Nicola Sturgeon is on Tuesday due to set out her Government’s plan for potentially holding a referendum on Scottish independence.
In a speech last week, she said she would not “stand here and pretend that there’s not challenges to navigate through”.
The UK Government has repeatedly rejected a section 30 order – a clause in the Scotland Act that would allow for a legal referendum to be held.
Mr Jack spoke as he visited the Royal Highland Show near Edinburgh on Thursday.
He was asked about the paper published by the Scottish Government last week, the first in a series of documents intended to form its renewed prospectus for independence.
Mr Jack said: “The first paper was what she called a scene-setter, I responded saying we’ve seen it all before.
“There was nothing new there, there may be new things to come forward. But our position is not to get engaged in constitutional wrangling with the Scottish Government.
“We want to focus on the people’s priorities, on inflation rising, on the cost of living challenge, on the war in Ukraine.
“Those are the issues we would like to focus on and we would like the Scottish Government to focus on their issues – failing schools, the backlog in the NHS or on Covid.”
Asked if a different wording of the proposed question on independence would change his mind, he said: “I’m going to cross that bridge when I come to it.
“I don’t know what wheeze she’s going to come up with on Tuesday but I’m very clear that the constitution, rather like Trident and our nuclear deterrent, these matters are reserved very clearly in the 1998 Scotland Act, they’re reserved to the Westminster Government.”
On rural matters given his attendance at the Royal Highland Show, Mr Jack was asked about the impact of Brexit and the changes to the Northern Ireland Protocol on farming.
He said: “We are dealing with the Northern Ireland Protocol through green and red channels, which we think is a very sensible way to solve the problem.
“Regarding Brexit, since Brexit, we’ve seen a rise in prices in milk, in lamb, in beef, so although costs have gone up, farmers are seeing the prices they get for their produce going up.”
He said the UK Government is working to bring down energy costs, which would help farmers through the prices of commodities like fertiliser.