TomTom's plan to buy its main map supplier, Tele Atlas, may be scuppered by the EU.
According to Reuters, European authorities have sent a formal "statement of objections" to the SatNav system manufacturer.
TomTom - which is now the world's biggest maker of car navigation devices - was aware of possible objections to the deal on grounds on competitions laws.
It therefore sent in some possible remedies to the EU to try and head off these concerns.
However, Reuters reports that the European Union executive "was unable to accept them before the deadline for sending the 'statement of objections', which lays out competition problems with the deal".
TomTom must now respond to the EU objections before the decision deadline on 5 May.
Reuters continues that if the buy-out is allowed to take place, it will mean that TomTom can move beyond hardware where growth is expected to decline.
The news service adds that Tele Atlas also supplies online mapping websites such as Google Maps, as well as maps to Nokia.