Frankfurt, which has been synonymous with one of the world's biggest auto shows, the IAA, for more than 70 years, has been eliminated from the race to host the next event in 2021, organisers said on Wednesday.

The next IAA International Motor Show -- which alongside similar events in Geneva and Detroit is traditionally one of the most important dates for world's car industry -- is to be held in Berlin, Hamburg or Munich, the VDA auto federation said in a statement.

VDA said that the decision "was not an easy one. For nearly 70 years, the metropolis on the Main river was the city of the IAA and, internationally, it was known as the 'Frankfurt Motor Show'."

The federation thanked the city -- which is also Germany's financial capital and home to the European Central Bank -- for its "long, excellent and trusting partnership."

Frankfurt is synonymous with the IAA International Motor Show
Frankfurt is synonymous with the IAA International Motor Show dpa / Boris Roessler

Nevertheless, observers said the decision did not come as a complete surprise as the last IAA in 2019 was marred by the absence of a number of major international automakers and a sharp drop in visitor numbers.

The IAA is held every two years, alternating with a car show in Paris. And like the events in Geneva and Detroit, organisers have found it increasingly hard to attract exhibitors.

Auto shows are very expensive, and manufacturers are increasingly baulking at the cost, particularly at a time when they are having to plough huge amounts into the development of electric vehicles and other future modes of transport.

The VDA nonetheless hailed "great interest in the new IAA" and said that the competition to be the next host city will be "a very tight race."