March 28 (Reuters) - Airbus, Chief Financial Officer Thomas Toepfer stressed the importance of a stable relationship with supplier Spirit AeroSystems, in a newspaper interview published on Thursday, as rival Boeing mulls plans to buy the firm.

"It is important that we have a stable relationship with this supplier," Toepfer told Switzerland's Boersen-Zeitung.

"The timetable that Boeing has is difficult to predict," he said, when asked when he expects clarity on the deal. (Reporting by Andrey Sychev, Editing by Rachel More)