It's over recent Census results, which showed a decline in the number of Welsh speakers.
The Welsh Government say the building remains open to staff and visitors as usual.
Cymdeithas are holding a peaceful protest at one of the entrances at the Welsh Government offices in Cardiff. The main reception remains open as usual to all staff and visitors.
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The area came fourth behind Peru, New Zealand and Portugal.
A charity match is to be held later tonight to raise funds for a former Cardiff Devils player with a terminal neurological condition.
Staying rather cloudy for much of the day in the south, perhaps with a little rain at first.