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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Friday night is not looking the brightest, and I am sorry to say there is worse to come for the start of the weekend!
Wales' Women face their first clash of the Six Nations against defending champions Ireland Saturday at Donnybrook
The body of John Sabine was found behind flats on a council estate in Beddau, near Pontypridd, last November.