Honda's Formula One boss Yusuke Hasegawa has said that the manufacturer is "discussing the possibility" of supplying a second team in 2018.
Currently, the Japanese marque only has an agreement in place with McLaren, having returned to the sport with the team in 2015.
Now they hope to have a decision in place "around the time of the Monaco Grand Prix" as to whether they will expand their engine supply portfolio.
"That's when Red Bull and Toro Rosso announced they would use the Renault engine this year," Hasegawa told Autosport.
"That is the latest timing for us but the earlier we know, the better."
"Now we are discussing the possibility of cooperation and the chance to supply the engine but so far, there is no fixed negotiation," he said.
Hasegawa also revealed that there had been some tentative interest from other teams, although he hinted that none of the interested teams were current Mercedes customers.
"There has been informal interest. They are very kind to show some level of interest," he said. "Mercedes customers have no strong intention to change their engine to Honda."
"We have to prove we can show a decent step in the performance of the Honda engine," he admitted. "Until then, I don't think they can show us a concrete request."
Bahrain International Circuit - Winter testing