About 700,000 Seat cars are fitted with the software that allowed parent company VW to cheat US emissions tests, the company says.
A Seat spokesman said they are currently trying to work out how many were sold in each national market.
In Spain slightly over 3,000 new cars are affected but showrooms have been told to put them aside.
VW said it would inform customers “in the next few weeks and months” about how refits would take place.
Seat also said it planned to contact owners so their cars can undergo tests.
It will also set up a search engine on its website to allow customers to find out if their vehicles are affected.
The Spanish automaker said it had temporarily suspended the sale and delivery of all new vehicles with the EA 189 engines which contain the software.
Numbers of cars affected by emissions scandal:
- VW – 5 million
- Audi – 2.1 million
- Skoda – 1.2 million
- Seat – 700,000
- Vans – 1.8 million