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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Surf Snowdonia, which features the first ever publicly accessible surfing lagoon, is to open in the Conwy Valley this weekend.
Cardiff's bus station will close this Saturday after more than 60 years serving bus passengers from across the country and the world.
Not a bad way to end the week! Plenty of sunshine out there to start, with the risk of a few showers in the north and west this afternoon.