Joe Kaeser, chief executive of German conglomerate Siemens, launched Wednesday a rare broadside against the European Commission, complaining that "backwards-looking technocrats" threatened to block a planned rail merger with France's Alstom.
Green lights for major tie-ups are usually negotiated quietly behind closed doors in Brussels.
But the Siemens-Alstom battle has been fought out in public, with Kaeser and his backers in the French and German governments on one side and EU Competition Commissioner Margrethe Vestager on the other.
"It will be interesting to see if the future of mobility will be determined by backward-looking technocrats or future-oriented Europeans," Kaeser told reporters at a press conference on the group's first-quarter results.
That sentiment echoed a tweet he directed at Vestager Monday, telling the Danish politician that "it must be bitter to be technically right but to do everything wrong for Europe" -- an apparent acknowledgement the Siemens chief expects the merger to be blocked.
Kaeser is unusual among German bosses for taking strong public political positions, including against far-right party Alternative for Germany (AfD).
Now, four months ahead of the European Parliament elections, he has turned his ire on the EU.
"Many people complain that Europe is not establishing itself as a powerhouse", faced with new challenges from abroad, he lamented.
Liberal politician Vestager has well-known doubts about whether competition from Chinese rail behemoth CRRC is pressing enough to justify waving through the creation of a European giant, which would have operations in 60 countries and annual turnover of 15.6 billion euros ($17.8 billion).