A letter calling for the Welsh language to be given official status under new assembly laws has been signed by 80 prominent Welsh public figures.
Signatories include the Archbishop of Wales, Barry Morgan, authors Rachel Trezise and Jan Morris, and poet Gillian Clarke.
The letter questions why the new draft measures do not contain a statement conferring 'official' status for Welsh.
The assembly government said the legislation is still under scrutiny.
In the letter to the heritage minister, Alun Ffred Jones, its authors state: "Unconditional declarations of official status are common throughout the world.
"Their intention is often to strengthen the situation of indigenous languages which have been oppressed. It is not clear why this step cannot be taken for the benefit of Welsh in Wales."
The letter's writers said that while they welcomed legislation in favour of the language, the language would only be official in specific contexts.
They said: "We are concerned that there could be harmful consequences for Welsh in broader contexts where it will be without official status.
"Although the amendments speak of not treating Welsh less favourably than English, the wording does not give Welsh equal status nor equal validity with English."
Others who have signed the letter include lawyers, actors and academics, including 11 professors.
An assembly government spokesperson said the current language measures being considered were still undergoing scrutiny in the assembly, and ministers were listening carefully to comments being made on the issue.
The spokesperson added that through the amendment process, clear statements on the status of the language were being made, and more importantly, the ways in which the language would have legal status.