Formula One champions Mercedes say they are dealing with engine issues ahead of the new season but expect everything to be fixed by the first race.

The comment, in a team interview with engine head Hywel Thomas, drew some wry comments on social media from those who recalled the sport's dominant manufacturer saying something similar last year.

Mercedes won 13 of 17 races in 2020 - Lewis Hamilton triumphant 11 times on his way to his seventh title - and have won the last seven constructors' and drivers' championships, a Formula One record.

"We have got some issues with the power units; we know we have issues but we have plenty of plans in place to fix all of those issues," said Thomas. "I'm sure it will all be ready for the first race."

The season starts in Bahrain on March 28.

Mercedes are supplying engines to four of the 10 teams this year, including their own, after McLaren switched from Renault power. Their other clients are Williams and Aston Martin (formerly Racing Point).

Thomas said this year was the first winter where Mercedes had limits on the amount of time they could test engines on the dyno.

"Also it's the first winter where we have prepared for only one single upgrade for the whole season," he added. "So we have to get all of our performance into the first Power Unit that goes to the first race.

"We have to get absolutely everything there for the first race and make sure its completely reliable."

This season has a record 23 races scheduled, although the COVID-19 pandemic makes that uncertain, but teams are allowed the same number of power units as previously - making reliability more of a factor.

Thomas said the pandemic had posed extra challenges and problems but IT solutions had made the team more effective in some areas.