The European Commission needs more information before it can decide whether to clear the MCI-Worldcom merger, it said.
The EC has decided that the notification of the merger of the two communications giants is incomplete, and will have to renotified during January, a spokesman said.
The Commission did not have enough information to make a decision, under EU merger regulations, on whether to clear the deal at the end of a month's initial examination or open a second phase in-depth inquiry, he said.
"At the services level we declared the notification incomplete and asked for complete information. Once we get the information the whole procedure will start again at day one," he added.
The spokesman could not say what information the companies had not provided.
The merger was first notified on 20 November and under merger regulations a Commission announcement is normally scheduled after a month.
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