Papua New Guinea's government remains in crisis with Prime Minister Peter O'Neill and his predecessor, Sir Michael Somare, both claiming to be the country's legitimate leader.
The Supreme Court on Monday ruled that Mr O'Neill was illegally appointed, while Sir Michael was overseas receiving medical treatment and ordered he be reinstated.
The ABC reports Mr O'Neill and 60 other MPs broke through a police barricade at Government House on Tuesday afternoon in Port Moresby and demanded to speak to the governor-general.
Through his secretary, Sir Michael Ogio urged the parties to sort out the issue among themselves.
But Mr O'Neill claims he is still the legitimate prime minster and says he is not backing down.
Despite Monday's supreme court ruling, parliament resumed on Tuesday morning with Mr O'Neill and his supporters occupying the government side of the chamber.
Speaker Jeffrey Nape made a brief statement reiterating that retrospective laws passed on Monday meant Sir Michael was not the prime minister and no longer an MP.
He said Sir Michael, 75, was now an ordinary person and Mr O'Neill was PNG's legitimate leader.