Citroen is leaving the world rally championship with immediate effect after six-times world champion Sebastien Ogier announced his departure from the team, the French manufacturer said on Wednesday.
Citroen Racing said it had made the decision "due to the absence of a first-class driver available for (the) 2020 season" but commercial factors were also a major consideration.
The motorsport.com website said Ogier was expected to be announced as a Toyota driver on Monday.
Toyota's Estonian Ott Tanak won the driver's title in Spain last month, ending Ogier's six-year reign, but announced four days later that he was joining Hyundai for 2020.
Hyundai secured the manufacturers' crown when this month's season-ending Australian race was called off due to the threat of bushfires.
"Our decision to withdraw from WRC programme as early as end of 2019 follows on Sebastien Ogier's choice to leave Citroen Racing," said Citroen CEO Linda Jackson.
"We obviously have not wished this situation but we could not imagine 2020 season without Sebastien."
Citroen won nine successive drivers' titles with Sebastien Loeb and Ogier between 2004 and 2012 and eight manufacturers' championships.
This season they and Ogier, who had returned after starting out with Citroen in 2009, ended third overall in both championship standings.
The marque had been expected to leave the championship in the coming years anyway, with PSA Group stablemates Peugeot announcing last week their return to the World Endurance Championship in 2022 and the Le Mans 24 Hours in 2023.
Citroen's premium DS brand is also a partner of champions Techeetah in the all-electric Formula E series, which is seen as a better fit for the auto industry's move towards future electrification.
Running three top level campaigns was considered too much of a stretch.
"When you see how much we need to push for the electrification of our brand and products and the marketing we need to push these cars on sales, it's really difficult for a brand like Citroen not to focus on this," Citroen team boss Pierre Budar told motorsport.com.
"And if the sporting discipline cannot help it's a real problem."
Finland's Esapekka Lappi, who also drove for Citroen this year, expressed disappointment at the decision.
"I'm not going to lie, this is very bad news for me, for us and whole rally family. I feel sorry for the staff and the fans," he said on Twitter. "Work has started to find other seat for next years. Not much time but I have a good and strong team around me."