Claire Williams has confirmed under-contract driver Valtteri Bottas could be allowed to join Mercedes, provided his current team's 2017 campaign isn't compromised as a result.
Williams' acknowledgement of Mercedes interest - and the possibility of doing a deal - comes on the heels of the German marque clarifying it would not announce a replacement for F1 champion Nico Rosberg until January 3 at earliest.
It also goes against Williams tech chief Pat Symonds' insistence that Bottas is "crucial" to Williams' 2017 plans.
It was a decision that Mercedes higher-ups admitted had caught them off-guard, the team faced with an urgent search for a teammate to Lewis Hamilton for 2017.
Bottas - whose career is managed by a team that includes Mercedes F1 boss Toto Wolff - was thought to be high on the list of candidates from the very beginning.
"I'm delighted to see that a team like Mercedes lists Valtteri as a potential replacement for Nico," Claire Williams, deputy principal of the Williams F1 team, told BBC Sport.
"We have always known Valtteri is one of the sport's key talents and are proud that the championship leaders recognise this.
"However, Williams has its own ambitions and we must always ensure we give our team the best opportunity to move forward. Any changes would only be made if Williams remains in a strong position to compete and develop in 2017."
The Williams team, which has its engines supplied by Mercedes, had announced a line-up of Bottas and 18-year-old Canadian rookie Lance Stroll for 2017.
Parallel to Mercedes' interest in Bottas, the Grove-based team is set to hire the German F1 squad's current tech chief Paddy Lowe.
Williams newcomer Stroll was to replace retiring F1 veteran Felipe Massa in the line-up - but the Brazilian could now feature on next year's F1 grid after all.
"If we did allow Valtteri to leave, we would only do this if an experienced, credible alternative was available, such as someone like Felipe Massa, for example," Williams was quoted as saying the same day as a report in France's L'Equipe suggested her team was indeed in talks with the Brazilian over a 2017 return.
"Whatever we decide, it must be in the best interests of this team."
Should Williams allow Mercedes to sign Bottas for 2017, it will come as a heavy blow to the German marque's protege Pascal Wehrlein, who was the other main contender for the seat, and who would instead likely look to Sauber or Manor to continue his F1 career.