Failing to prove his majority twice, controversially appointed Sri Lankan Prime Minister Mahinda Rajapaksa on Sunday demanded holding a snap parliamentary polls to end the ongoing political crisis in the country.

The island nation is witnessing a political crisis since President Maithripapala Sirisena's controversial move to sack prime minister Ranil Wickeremesinghe and install Rajapaksa in his place on October 26.

Sirisena later dissolved Parliament, almost 20 months before its term was to end, and ordered snap election. The Supreme Court overturned Sirisena's decision to dissolve Parliament and halted the preparations for snap polls.

Both Wickremesinghe and Rajapaksa claim to be the prime ministers. Wickremesinghe says his dismissal is invalid because he still holds a majority in the 225-member Parliament.

In a statement, Rajapaksa cites occasions in the history when Parliament had been dissolved to call parliamentary elections in Sri Lanka to avoid crisis and bring in political stability.

"The only way to restore stability to a destabilised democracy will be through a general election. According to our Constitution, sovereignty is vested in the people and not in Parliament," the former strongman said.

Rajapaksa has, so far, failed to prove his majority in Parliament.

Wickremesinghe, with the support from the main Tamil party, claims to have the support of more than 113 legislators, required for simple majority.

Speculation are that President Sirisena may remove Rajapaksa on Wednesday when another motion would be taken up in Parliament and is defeated.

Following the vote, Sirisena would be forced to appoint a new prime minister and a Cabinet.

The Sri Lankan president has said that due to sharp personal differences with Wickremesinghe he would not reappoint him as the Prime Minister.

However, Wickremesinghe's UNP claims that Sirisena will be left with no choice as he would be the man who will command the confidence in the House.

In the statement, Rajapaksa also slammed Wickremesinghe's UNP of feeling shy of contesting a fresh poll.

The UNP has said that any election now would be unconstitutional, without restoring the pre-October 26 status.