A U.S. government investigation showed no link between electronic throttles and unintended acceleration in Toyota Motor Corp vehicles, a victory for the world's top automaker battered by recalls over runaway vehicles.

The encouraging result for Toyota stems from a 10-month probe ordered by Congress following recalls of millions of its best-selling models in 2009 and 2010 over defective floor mats and accelerator pedals.

Some safety advocates and congressional investigators questioned whether software-driven throttles also played a role in unintended acceleration complaints.

There is no electronic-based cause for unintended high-speed acceleration in Toyotas, U.S. Transportation Secretary Ray LaHood said in a statement on Tuesday.

Although no defects were found in the Toyota throttles, regulators said they would consider imposing requirements for all vehicles to have braking systems that automatically counteract any instances of unintended acceleration.

Toyota, which has put electronically controlled throttles in its vehicles since 2002, has consistently said those systems are safe.

(Reporting by John Crawley and David Lawder; Editing by Tim Dobbyn)