Nepal's caretaker Prime Minister K. P. Sharma Oli was ejected from the country's ruling Communist party on Monday, his opponents said, in protest at his abrupt move in December to dissolve parliament and call for an early general election.

Despite being stripped of party membership, Oli remains in office.

Meanwhile judges in the Himalayan country's top court are hearing more than a dozen petitions from independent lawyers and Oli opponents on whether his move to dissolve parliament and call an early election was legitimate or unconstitutional. The court is expected to deliver its verdict next month.

The ruling Nepal Communist Party has split over Oli's call for a new parliament to be elected more than a year ahead of schedule on the basis that his colleagues were not cooperating with the government on policy interventions.

"We have expelled Oli from the party on the grounds that he was not following the party rules and was working against collective decision-making," said Pampha Bhusal, a senior leader of the faction opposing Oli.

But Surya Thapa, an aide to Oli, said the expulsion holds no political meaning as the leader continues to remain prime minister, adding that Oli was confident of a legal and political victory.

Oli says he represents the main ruling party after the split.