The chief inspector of Ofsted has said that trust leaders are responsible for school improvement rather than the inspectorate.

Speaking at the Confederation of School Trusts’ annual conference in Birmingham on Thursday, Amanda Spielman said she had heard criticism of Ofsted because teachers felt it had not improved their school.

“But as you all know, school improvement has not been part of Ofsted’s remit for more than a decade; that responsibility sits with you and to some extent with other parts of Government,” she said.

“A clear policy distinction has been drawn between inspection and improvement.”

She added that Ofsted had worked to be a “force for improvement” in recent years.

Ms Spielman also told the conference that they should not “be afraid to make curriculum changes because you’re concerned that inspectors won’t understand or might take a dim view”.

“Nothing could be further from the truth. In fact I encourage you to continue to work to understand your pupils’ needs, and to make the curriculum changes that they need with confidence,” she added.

She said that “significant challenges” remained when it came to helping pupils catch up from lost learning during the pandemic.

“At every stage, children have lower and more variable starting points. Gaps have widened; younger children are often behind in language, communication and social skills,” she said.

“We hear that more effort is having to go into teaching older children behaviour and routines and there is more work for you in managing behaviour.

“There’s still too much persistent absence and many vital SEND, mental health and other support services have yet to return even to their creaking pre-pandemic levels while needs continue to be exceptionally high,” she said.

She said that despite “all the challenges” of the previous two years, many schools had managed to improve, with more schools raising their Ofsted rating to “good”, although “some are losing a historic outstanding grade”.

Of the Schools Bill proposals for more accountability for academy trusts, she said: “I’m sure that many of you agree that the current accountability arrangements for trusts are not yet in the best possible shape.

“And Government has recognised this too with its plans to set a new regulatory regime.”