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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A top health boss has told ITV News that change is needed to hospital services in north Wales, that could include A&E.
A fine and bright start to the week, with any lingering rain clearing away as we move throughout the afternoon.
A wet and windy night to come, with rain turning heavier overnight. Feeling particularly blustery in coastal areas.