Flanked by a handful of his former ministers, Rajapaksa, 69, told his supporters that he was heeding to their demands to return to politics after he was defeated in the January presidential polls after spending a decade in power.
"We cannot reject the request you have put before us. We will contest and look to form the next government," he said.
The much publicised event at his deep southern province home of Madamulana came just a day after President Maithripala Sirisena made it clear that he would reject Rajapakse's request to be the prime ministerial candidate for the main opposition United People's Freedom Alliance.
Rajapaksa was thus unable to say under which political party he will look to contest and if he is still seeking the post of the prime minister. He was defeated by his former health minister and opposition unity candidate Sirisena, 63, who fought on the promise of large-scale political reforms, ethnic reconciliation and scrapping presidential executive powers.
Sirisena called the general elections last month to strengthen his position in the legislative assembly, where some of his key reforms are facing resistance from Rajapaksa loyalists.
Accused of siphoning off millions during his decade-long tenure, Rajapaksa and his family members are facing multiple allegations of graft under the new regime but banking on their tenure's success in bringing an end to the country's three decade-old civil war with the Liberation Tigers of Tamil Eelam.
Commenting on his successor's government headed by arch rival Prime Minister Ranil Wickremesinghe, Rajapaksa blamed the government for endangering national security and going soft on LTTE supporters.
An ethnic Sinhalese himself, Rajapaksa remains popular with huge sections of country's Sinhala majority but was shunned by world leaders and many local supporters for his autocratic style and refusal to investigate allegations of human rights violation during the last stage of war with LTTE in 2009.
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