"Continued uncertainty will hamper investment decisions", a key business organisation has warned.
It follows data out this morning showing the UK economy shrunk in April.
The British Chambers of Commerce said "businesses will be keen to see further action from the government", following the figures and the chancellor's spending review.
Stuart Morrison, the group's research manager, said: "The UK's partial trade deal with the US has offered some relief, but the lowering of tariffs on steel, aluminium and automotives is not yet fully assured.
"This continued uncertainty will inevitably hamper firms' investment decisions and long-term growth prospects."
Morrison said their own research has found more than four-in-five of businesses surveyed say the government's hike to employer national insurance contributions (NICs) will impact their operations.
He called for "a clear tax roadmap, covering national insurance and business rates" as this would give businesses "some certainty to plan for the future".
Morrison concluded: "Additionally, a timeline for when they might see practical changes to UK-EU trading arrangements would also be very welcome by firms navigating ongoing trade uncertainties."