Welsh lessons only for new pupils at four Carmarthenshire schools
Plans to make new pupils take lessons entirely in Welsh at four primary schools have been backed by councillors despite objections.
Education in English or Welsh would then be offered from the age of seven at the schools in Carmarthen, Newcastle Emlyn, St Clears and Whitland.
Carmarthenshire councillors said the changes would boost bilingualism.
Consultation showed some parents feared a lack of choice and claimed their children's English skills could suffer.
The schools concerned - Ysgol Llangynnwr in Carmarthen, Ysgol y Ddwylan in Newcastle Emlyn, Ysgol Griffith Jones in St Clears and Ysgol Llys Hywel in Whitland - are currently dual stream, where parents can choose whether their children are taught through the medium of English or Welsh.
Under the plan, foundation phase lessons would only be available through the Welsh language, according to the Local Democracy Reporting Service.
Defending the move to promote Welsh medium education, Trimsaran councillor Kim Broom said: "I think we are missing a trick or two by not promoting the success of children who go through it."
Councillor Glynog Davies, responsible for education at the Plaid Cymru-led authority, claimed the majority of children at the four schools come from outside the county.
But he added: "It is my duty to specifically provide an education for the people of Carmarthenshire and to promote Carmarthenshire's language policy."
Mr Davies said the council wanted children to be confident in both languages when they reached the age of 11.
The changes backed by the education scrutiny committee will come into force next year, if approved by Carmarthenshire's ruling executive board later this month.