Organisers have insisted that the ATP Tour event is not in danger of falling off the calendar. The tournament is scheduled to be staged in October in Vienna and it is hoped that a new sponsor will be found within the next few weeks.

Tournament director Herwig Straka told the Associated Press that the bank’s decision “has emerged over the past couple of weeks and has not come as a surprise to us”. Straka added: “We have started talks with other potential sponsors immediately.”

Bank Austria chief executive Willi Cernko explained to national newspaper Kurier that his organisation had decided to end its backing after the tournament’s host venue, Wiener Stadthalle, announced a sponsorship deal with Erste Bank, a rival of Bank Austria.

The first edition of the tournament took place in 1974, and sponsorship was introduced in 1976 after the event was cancelled due to a lack of financial support the previous year.

Fischer, a skiing equipment and tennis racket producer, sponsored the tournament for 10 years before Creditanstalt signed up as the lead partner in 1986. Bank Austria’s name was added to the tournament when Creditanstalt was acquired by the financial institution in 1997.