The ministers of Scotland, Wales and Northern Ireland highlighted a number of key finance issues in a joint letter to the Chief Secretary to the Treasury David Gauke.
They said there is a need for the UK Government to “engage meaningfully” with the devolved nations on the economic and financial implications of leaving the European Union, stressing its plans to exit the single market and customs union have caused “significant concern”.
The ministers also pressed Mr Gauke on the potential impact of cuts to public spending in 2019/20.
“We seek reassurances that you will not pass on further austerity and make additional budget cuts on top of the real-terms reductions in spending power that the devolved administrations are already facing,” they wrote.
In the letter, the ministers also called for the UK Government to announce the Budget earlier in the Autumn to allow greater time for devolved administrations to consider the impact on their own budgets well in advance of the start of the financial year.
Scotland’s Finance Secretary Derek Mackay said: “It is clear that the Scottish and UK economies are facing challenging economic circumstances.
“There is a greater need than ever for the UK Government to engage meaningfully with the devolved administrations on the emerging economic and financial implications of the Brexit vote.”
At the Autumn Statement last year, Chancellor Philip Hammond announced plans to move the budget to autumn and have a smaller financial update in the form of a Spring Statement.
Mr Mackay said: “We would welcome a commitment to engage with us in developing the approach to the new budget timetable and ensuring that steps are taken to support rather than undermine devolved budget processes.”
The Welsh Government’s Finance Secretary Mark Drakeford said: “The possible impact of the £3.5 billion of cuts the UK Government have planned for 2019/20 could generate critical cuts to all our budgets.
“By speaking with one voice, we hope the UK Government can provide clarity on how it intends to find these savings and the resulting impact on our Budget.”
Stormont Finance Minister Mairtin O Muilleoir said the “austerity agenda already places severe burdens on devolved budgets and further cuts in 2019/20 would be unacceptable”.