Replacement vehicles have been ordered but will arrive after 1 June, when the council will begin issuing penalty charge notices for non-compliant vehicles entering the zone.
The authority said it will hire vehicles to ‘ensure business continuity’, including 14 welfare buses, which will not all arrive until September.
Transport and environment convener Scott Arthur said he was disappointed that the council had missed a target it expected others to meet.
He said he had asked that no non-compliant vehicle enters the LEZ.
Edinburgh has a further 35 non-complaint vehicles that are not required to enter the city centre zone, which are due to be replaced but not as a priority.
The Scottish Government set out plans to introduce a LEZ in Edinburgh in 2017, and the zone was introduced in May 2022, with a two-year grace period before enforcement.
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