Toto Wolff has denied Mercedes is struggling with an engine reliability problem ahead of the 2021 season.

The title-winning team supposedly 'turned down' its engines when Max Verstappen dominated the season ending Abu Dhabi GP, and Mercedes engine boss Hywel Thomas said recently there had been "problems" with the unit ahead of the new calendar.

"We don't have any particular problems with the reliability of the power unit," team boss Toto Wolff now insists.

"Of course, the operation of the power unit at peak power for a long time gives us a lot of information for study, but we have everything under control," he insisted.

"For some years we had problems with engine cooling, but this was because our pre-season simulations did not accurately reflect what was happening on the track.

"I believe we have now made a big step forward in this direction," said Wolff.