Oracle has failed to persuade the European Commission that it will provide a safe home for MySQL.
The Commission is currently looking at Oracle's takeover of Sun, and has previously said it is especially worried about the fate of free database MySQL.
A spokesman for Competition Commissioner 'Steelie' Neelie Kroes said the Commissioner had: "expressed disappointment that Oracle had failed to produce, despite repeated requests, either hard evidence that there were no competition problems or, alternatively, proposals for a remedy to the competition problems identified by the Commission", according to the Beeb.
The comments were made to Oracle president Safra Catz during a meeting in Brussels. The EC said it was happy to move quickly to approve the deal, provided its concerns over MySQL were met.
Without further reassurance the Commission could block the takeover or at least order Oracle to sell off the free database business first. This would put Europe at odds with US regulators which have already given the deal the go-ahead. The US initially said it was concerned about how Java would be licensed.