Urenco UK Ltd (UUK) has rectified shortfalls in their international transport of packages of enriched uranium.
The Office for Nuclear Regulation (ONR) served an improvement notice on the company in April after inspections revealed they had not undertaken sufficient checks before shipping to ensure that the correct legal requirements and competent authority approvals had been met.
UUK, based in Capenhurst, Cheshire, has now complied with the improvement notice.
There were no consequences to the public or the environment as a result of these shortfalls.
The enforcement action was taken under The Carriage of Dangerous Goods and Use of Transportable Pressure Equipment Regulations 2009.
Nick Blackburn, Principal Inspector from ONR's Transport Competent Authority, said: "Since serving the notice we have worked closely with UUK and are satisfied that they have complied with the notice by addressing this transport shortfall.
"All companies involved in the transport of Class 7 dangerous goods, including all sub-contractors within a scheduled operation, must ensure their legal provisions to provide this service are compliant with current legislation."