McLaren has made an exploratory approach to Mercedes about an engine supply, according to the BBC.
McLaren endured a problematic pre-season with its Honda power unit, which was plagued with reliability issues and was lacking performance compared to its rivals. A frustrated Fernando Alonso, whose contract with McLaren expires at the end of 2017, labelled Honda the team's "only problem" coming into the new season.
Honda has since downplayed its chances of rectifying its performance deficit in time for the Australian Grand Prix on March 26, leading to questions about Alonso's future and whether McLaren should look for a new supplier.