Attorney-General George Brandis says his colleague Barnaby Joyce will escape disqualification from Parliament, despite holding New Zealand citizenship in breach of the constitution, because Mr Joyce was unaware of his dual-citizen status.

The Deputy Prime Minister's case has been referred to the High Court, along with that of his colleague, Nationals Senator Matthew Canavan, who has stood aside from cabinet until the matter is resolved.

Mr Joyce is refusing to stand aside from cabinet while his position is clarified. Labor says Mr Joyce should not be in cabinet or vote while there is the chance his position could be invalid. But Prime Minister Malcolm Turnbull told Parliament on Monday, that: "the leader of the National Party, the Deputy Prime Minister, is qualified to sit in this House and the High Court will so hold."

On Monday night, Senator Brandis rejected suggestions Mr Turnbull's comments predicting the High Court's ruling were a directive to the bench.