The Seat Exeo and Exeo ST (estate version) will go off sale within the next few months.
Both models are based on the previous-generation Audi A4 and went on sale in the UK in April 2009.
Seat said: 'The Exeo was always expected to have a shorter model life than usual, because it was built as a bridging model.'
With the recent arrival of the all-new Seat Toledo, the Exeo saloon looks dated and is expected to be withdrawn very shortly. The Toledo hatchback is of similar size to the Exeo saloon, but with more modern underpinnings.
The Seat Leon ST is due to be unveiled later this year with sales starting before the end of 2013. It is of comparable size to the Exeo ST, which will be withdrawn from sale in the middle of the year to make way for the new estate.
The Seat Toledo is on sale now and prices start from 14,120. Prices and specifications of the Leon ST will be released nearer its launch date.