Nationals split from Coalition government!?

Australia's Deputy Prime Minister Barnaby Joyce says the Nationals didn't sign the Cop26 communique.

So, signing that isn't a government policy? They can't have cabinet positions and pick and choose when to be part of the government.

Doesn't this mean the Nationals split from Coalition government.

Shouldn't they move to the Cross Bench en masse and resign from ministerial positions?

The government is a shambles.