Headteachers have said that Ofsted inspections will need to be suspended if the coronavirus outbreak leads to major staff and pupil absences.
The Association of School and College Leaders (ASCL) general secretarysaid that it would be unfair to carry on with "high-stakes inspections" in these circumstances as they would not provide a genuine view of the school.
Mr Barton also said that schools' attendance figures should not be measured by the government in the same way this year.
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Speaking ahead of ASCL's annual conference, he said there was already evidence of parents not sending their children to school because of concerns about the coronavirus.
On Ofsted inspections, he said: "[With] so much of this, you are not sure of the scale of it, but if you have a school where lots of children or a fair number of your children are not there or some of your middle leaders are not there, by definition, you are not going to get your regular Ofsted inspection.
"Given the high-stakes nature of Ofsted, I think it would be unfair if we assumed that those reports were somehow business as usual or that inspection could tell you anything genuine and authentic.
"One of the things we would be saying, just as we have been since with performance tables and attendance, is that there will be a point where we should suspend inspection in its current form, but that is some way down the line."
Mr Barton has already called for Sats and performance league tables to be scrapped this year if schools are forced to close.
Speaking to media after his speech at the ASCL conference Education Secretary Gavin Williamson said that schools would not be penalised for absences "because of things that completely outside of their control."