Malcolm Turnbull no longer has a majority on the floor of parliament, Labor frontbencher Anthony Albanese says.
The High Court has found Deputy Prime Minister Barnaby Joyce to be disqualified from sitting in parliament due to his dual New Zealand citizenship.
"What we've seen is the government has lost its capacity to govern over recent months," Mr Albanese told Sky News on Friday.
"Today they've also lost their majority on the floor of the House of Representatives."
Mr Joyce and Malcolm Turnbull, who expressed confidence his deputy would be cleared by the court, had been "humiliated".
Mr Joyce told reporters in Tamworth: "In my gut I thought this is the way it was going to go."
Mr Albanese, who has been calling for Mr Joyce to stand aside from the cabinet while the court deliberated, said such a comment was "breathtaking".
"What he is saying with that statement is that he has sat illegitimately in the parliament, thinking to himself, 'I shouldn't be here'," Mr Albanese said.
"That is an extraordinary proposition that he has not only continued to sit in the parliament, he has continued to sit as a minister, as the deputy prime minister and as - importantly - acting prime minister of the nation."
Asked what Labor would do if the government sought to suspend the parliament until after a by-election in Mr Joyce's seat of New England, Mr Albanese said it would be "red hot".
