(Reuters) -Belgium's top administrative court on Wednesday rejected Alstom's request to suspend national rail operator SNCB's decision to name CAF as the preferred supplier for its AM30 train contract.

"The Council of State estimates, after an interim review, that none of the criticisms made by the company challenging the legality of this appointment decision were serious," it said in a statement.

CAF was appointed as the preferred bidder against French trainmaker Alstom and Siemens of Germany at the end of February.

In April, the court suspended the order following Alstom's appeal against the decision.

"We are disappointed by this decision and by the fact that our arguments have not been taken into account. We do not wish to communicate further on this subject," Alstom said in an emailed response to Reuters.

The order plays a crucial role in determining the future of Alstom's Bruges facility, which faces the threat of restructuring and possible closure.

SNCB's tender, the biggest the company has placed, consists of a first batch valued at 1.7 billion euros ($2 billion), with optional batches potentially bringing the total contract value to 5 billion euros.

Earlier this month, the Council rejected Siemens' separate appeal against SNCB's decision. 

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