Liz Truss has admitted she should have "laid the ground better" for her mini-budget, after it sparked days of market turmoil.
The prime minister told the BBC's Laura Kuenssberg she had "learned from that", but she was confident her tax cutting package would boost economic growth.
She added a decision to cut the top earner tax rate was a "decision that the chancellor made".
And she revealed it was not discussed with the whole cabinet beforehand.
The cut to the 45p rate has provoked outrage from opposition parties, and concern from some Conservative MPs.
Former minister Michael Gove said the cut displayed the "wrong values," and signalled he wouldn't vote for it.
He also said he was "profoundly concerned" about the decision to borrow to fund the tax cuts, calling it "not Conservative"Liz Truss admits disruption after tax cut pledges
Climb down or stand firm - what does Truss do next?
Communication key for Liz Truss as MPs gather
The government's mini-budget included £45bn in cuts funded by government borrowing, and revealed the government expects its two-year scheme to fix energy prices will cost £60bn in the first six months.
The announcements sparked days of turbulence in financial markets, with the pound falling to a record low against the US dollar on Monday, although it has since recovered.
The rocky economic backdrop is set to dominate this week's Conservative party conference, Ms Truss's first as Tory leader, where she faces the task of reassuring her MPs over her approach to boosting the flagging UK economy.
Speaking from the gathering in Birmingham, Ms Truss promised to win over "the hearts and minds" of Tory MPs to persuade them of her plan.