Toto Wolff says Mercedes will think about its 2020 driver lineup after the summer break.
Lewis Hamilton is staying, but there is a big question mark about the identity of his teammate.
Valtteri Bottas might struggle to hang onto his seat, particularly with Esteban Ocon in the wings and sensational rumours that Max Verstappen could leave Red Bull.
"We don't want to put pressure on ourselves to make the driver decision before the summer break," team boss Wolff told Speed Week.
Frenchman Ocon is being linked with a potential loan to Renault.
"Esteban is arousing the interest of some teams," Wolff confirmed. "We don't want to give him up lightly.
"But if there is no chance of a place for him with us, we must let him go."
As for the other Mercedes development driver, George Russell, Wolff says he is staying at Williams for 2020.
"George has an ongoing contract with Williams for 2020, and I hope he helps to bring them forwards," he said.
