Tesco's automated tills will now speak both Welsh and English
Shoppers at branches of a supermarket chain will now be able to use self-service checkouts in Welsh following demand from customers.
Tesco said a programme that was started in the summer to convert the automatic tills was now complete.
The Heritage Minister Alun Ffred Jones said: "It is important that we give Welsh an opportunity to grow and adapt to the modern environment."
The announcement coincides with the European Day of Languages.
Tesco runs 74 stores in Wales and most of them now provide self-service checkouts.
Before the change, these tills spoke only in English.
But now customers will be able to hear instructions in a Welsh female voice.
Mr Jones said: "I am happy to see private sector businesses increasing the use of Welsh in their stores and responding to the need for user-friendly Welsh language services."
"I would like to see more businesses and organisations promoting their services bilingually and allowing Welsh speakers and Welsh learners to be able to shop, learn, work and play in their own language."
Felix Gummer, the Tesco's corporate affairs manager for Wales said the change allowed the supermarket to "serve communities in the best possible way".
"In response to customer demand and multilingualism in Wales all our new stores signs have been fully bilingual for some time, but today is a further step forward as we have listened to the views of customers for more services to be in Welsh.
"This roll out programme which started this summer is now complete."
The change was also welcomed by Cymdeithas yr Iaith Gymraeg, the Welsh Language Society.
Dafydd Lewis from the society said: "We've been in discussions with Tesco and large similar companies and this is one of the things we've been asking them to develop. This is a first step towards developing a full language policy.
"What we'd really want is a language act that would mean all companies in the private sector developing a Welsh language policy without having to have any pressure put on them," he added.
A spokeswoman for the supermarket Morrisons said there were no self-service checkouts at its stores in Wales.
The European Day of Languages was launched in 2001 by the Council of Europe, with the aim of promoting language learning and widening the range of languages learnt.
This year also marks the tenth anniversary of the European Charter for Regional or Minority Languages.