In addition to Welsh and English, Mudiad is hoping to offer Spanish or French when the group's new pound;2.1 million centre in Aberystwyth opens within the next six months.
Mudiad, which caters for 12-15,000 children annually - 7,500 of whom go on to attend Welsh-medium primaries each September - practises the immersion method of teaching and would like to make its headquarters a trilingual facility.
"We have still to decide between French and Spanish," said chief executive Hywel Jones. "French would probably be more useful but Spanish is more phonetic and therefore more akin to Welsh.
"At this age a child is like a sponge. They can assimilate languages easily and switch from one to another. Most will be fluent by the time they reach primary school and it will be very useful for them to have other languages."
Such a policy has been welcomed by CILT Cymru, the organisation set up to promote foreign language learning in schools.
It has been piloting French and German lessons for Years 5 and 6 primary children. But Richard Parsons, CILT Cymru's key stage 2 project co-ordinator, believes children should be taught new languages earlier.
"The fact that they have two languages is not a barrier to learning a third or a fourth," he said. "At age three to four, learning another language is water off a duck's back. Our primary foreign language pilot has received an extremely positive response from parents and pupils."
CILT Cymru is also working hard to ensure that additional languages learnt in the early years are not lost at a higher level. "Where clusters of schools are strong, the primary schools work with the secondaries to ensure children make the most of what they have already learnt," said Mr Parsons.
In addition to trilingual provision for 105 infants in two nurseries, Mudiad's new centre will have a sensory room and garden for all children - not just those with special needs - a music room and an arts and crafts room.
Mr Jones said the main aim was to give as many parents as possible the opportunity to have their children taught through the medium of Welsh.
"We found that 75 per cent of parents who send their children to our groups are non-Welsh speakers," he said.