Sirisena had suspended parliamentary proceedings until November 16 after abruptly firing Prime Minister Wickremesinghe and replacing him with Rajapaksa, a controversial former president, on October 26.
Rajapaksa is known as a Sri Lankan nationalist, while being close to China.
Prime Minister Mahinda Rajapaksa's legislator son Namal on Sunday indicated that the long held demand of the Tamil minority community to release all Tamil prisoners may be fulfilled soon, a move aimed at persuading the Tamil legislators to support Rajapaksa.
While the UNP and opposition political parties also had requested the President to reconvene parliament, a discussion was also held between the Speaker and the President recently.
Thousands of Sri Lankans have marched in support of a new government led by the country's former strongman, highlighting the political polarisation in the Indian Ocean island nation. On Sunday, Sirisena said parliament would be recalled on November 14.
Al-Jazeera reported, while quoting sources, that the decision drew strong criticism from the supporters of the country's ousted Prime Minister Ranil Wickremesinghe 's United National Party (UNP), who even termed the order to be "too late".
The speaker in Sri Lanka's parliament said he can't recognize newly-appointed prime minister Mahinda Rajapaksa until he proves a majority in the legislature.
He said that a majority of lawmakers in the 225 member Parliament were of the opinion that the recent changes made in the Parliament were undemocratic and inconsistent with Parliamentary traditions.
Sirisena and Rajapaksa arrived at the rally amid loud cheers. Parliamentarians are also favouring the ousted PM along with the speaker.
"For the past three and a half years, poor people were suppressed by Ranil Wickremesinghe's economic and political vision".
"Foreign countries are trying to take our resources, take our land", said Mithra Kumara Jayasinghe, a wedding photographer at the rally who said he had voted for Rajapaksa the two times he was elected president, in 2005 and 2010, and when he lost a re-election bid in 2015.
He said he fired the prime minister because Wickremesinghe was trying to implement "a new, extreme liberal political concept by giving more priority for foreign policies and neglecting the local people's sentiment".
The alliance had "decided to vote in favour of the no-confidence motion against Rajapaksa", the statement said.
The UNP has handed over a motion of no trust against Rajapaksa.
Jayasuriya said it would be "inappropriate" for him to side either way - but official sources said he took the unusual step to avoid publicly clashing with Sirisena.