The Congress, in the recently concluded election, ended the BJP's 15-year rule in the state.
"Mai yahi tha aur yahi rahunga (I was here and will stay here)," Mr Singh said at a press conference.
"Now I will keep on coming to the BJP office in my new role. I will be meeting the press more often. Earlier as a chief minister, there were certain limitations for me but now I will come to party office and keep on meeting my workers," a smiling Singh said.
He also touched on the Supreme Court's ruling on the Rafale issue, and slammed Congress chief Rahul Gandhi.
"For the last eight months, as part of a well-planned conspiracy, an attempt was being made to malign the image of Prime Minister Narendra Modi by levelling false charges."
"The Supreme Court's decision has exposed the lies of the Congress president," he said.
The Congress, itself embroiled in corruption scandals, was spreading lies against the BJP and the prime minister who has been discharging his duty with complete honesty, he said.
Rahul Gandhi and his party should apologise, he demanded, saying that such a smear campaign against a prime minister was never seen earlier.
The Congress will pay for this in Lok Sabha elections, he said, seeking Rahul Gandhi's resignation as Congress chief.
Mr Gandhi had raised the issue of alleged irregularities in Rafale deal throughout his poll campaign in Chhattisgarh.
When asked if the issue had any impact in the elections, Mr Singh said, "There has been no assessment of its impact so far. But such issues which are based on lies should not be raised by the president of a leading party."
Asked about the Congress' promise of loan waiver to farmers, Singh said he will speak about it after ten days.
The Gandhi-led party had promised to waive loans of farmers within ten days of coming to power.
The Congress won 68 out of 90 seats in the Assembly elections.