A senior member of the Welsh Language Board has said a series of new laws are needed to create a bilingual Wales.
There have been calls for a new language act at this year's event
Professor Colin Williams called for language laws to be extended to include parts of the private sector including banks and insurance companies.
Since the 1993 Welsh Language Act, the public sector in Wales has had to provide a bilingual service.
Critics of further measures have said extending language legislation to the private sector would be "impractical".
In his speech at the National Eisteddfod - being held at the Faenol estate, near Bangor - Mr Williams said the Welsh assembly rather than Parliament should be given the powers to legislate and that language rights should also be enshrined in a new language charter. .
Mr Williams, whose speech on Thursday does not reflect the official view of the Welsh Language Board, said equal status for Welsh and English, increased powers to enforce existing laws, and an independent commissioner for the Welsh language could all be introduced in an attempt to create a fully bilingual Wales.
Currently, all public bodies must provide a bilingual service, but some campaigners want to see the same rules extended to include private firms.
But the Conservative MP and AM for Monmouth, David Davies, said calls for further Welsh language legislation undermined goodwill towards the language among non Welsh speakers.
He added: "If you gave everyone the right to speak Welsh wherever you went, you would shut down all sorts of businesses.
"We all know it's completely impractical but no doubt it will get a round of applause at the eisteddfod.
"Across the rest of Wales a lot of people are going to look at that and say it's madness.
"These sorts of calls undermine years of hard work."
Former Plaid Cymru president Dafydd Wigley told BBC Radio Wales that while he believed new measures were needed, some of the proposals were unrealistic.
He added: "The things that are reasonable are, for example, the right of Welsh-speakers in their place of work to converse in Welsh to each other.
"That has been denied in some places in the past.
"But the need to have people dealing with all the public all the time through a language they don't speak - that's unrealistic."
Mr Williams' eisteddfod speech is the latest debate on the Welsh language at this years event.
On Tuesday, First Minister Rhodri Morgan was followed around the site by members of Cymdeithas with placards and a loudhailer demanding a new Welsh Language Act.
Mr Morgan described protesters as "bullies" and said such tactics would never work.