Speaking to reporters in Guna, Madhya Pradesh, Mr Singh said, "I may contest the 2014 LS elections if the Congress allows me to do so."
Mr Singh had last contested the assembly elections in Madhya Pradesh in December 2003. At that time, he had announced that if his party lost, he would not contest any polls for another 10 years. The BJP had removed the ruling Congress from power at that time.
The Congress leader further clarified that he did not intend to contest the upcoming assembly polls in Madhya Pradesh.
"I will not contest next year's assembly elections in Madhya Pradesh, but I will make all the efforts to dislodge the ruling BJP government," he said.
Referring to BJP president Nitin Gadkari, who visited Lord Mahakaleshwar temple in Ujjain today, the Congress leader said, "Even the Gods would not bless the BJP chief, who is known to be corrupt."
He also took a dig at yoga guru Baba Ramdev, saying that he had no right to talk about Congress as he himself was 'very corrupt'. "I have always maintained that Baba Ramdev is a thug and there has been no change in my stand," he said.
Mr Singh also sought to know why Gujarat Chief Minister Narendra Modi was "hesitant" to talk about his private life. "If he had got married, he should accept the fact and if not, he should say that also openly," he said.
Talking about Bihar, Mr Singh said, the assistance the state has been receiving from the Centre now has increased six times as compared to what it was getting when its present Chief Minister Nitish Kumar was a minister in the NDA regime.
"It is strange that when he was a central minister, Nitish had never raised the issue of giving special status to Bihar," Mr Singh said.
Over the issue of revival of the National Herald newspaper, founded by Jawaharlal Nehru, he said the party had done nothing wrong in this connection. The Congress has admitted that it had given a Rs. 90-crore interest-free loan to Associated Journals Limited to help it revive the now-defunct National Herald.