"We have many issues. But the most important is of black money because the amount of money stashed abroad, if brought back, will help develop every village of the country. Every village will receive crores of rupees," he said.
Ramdev said both Congress and BJP are corrupt.
"I will give my support to Narendra Modi, only if he assures me of bringing back the black money. BJP, too, wants to bring it back and Modi personally is an honest person so, I think, he may give his consent on the issue," Ramdev said.
The Yoga guru said he will hold discussions with the BJP leadership on the matter before his proposed rally at Talkatora Stadium in Delhi on January 5.
He said a formal announcement of support to Modi at the rally will follow only after they agree on the issue.
Ramdev said both Congress and BJP are corrupt but the top leadership of the BJP has a clean image. "Modi has a clean image...his nationalism can not be questioned, while the same cannot be said for the Congress leadership," he said.