"It is Congress which presents a divided house and not BJP, which has never seen a vertical split," Rajnath told reporters. (Agencies)
The announcement regarding Modi will be made at an "appropriate time", he said.
Rajnath, who was here to address the Maharashtra BJP executive committee meeting, alleged the Congress-led UPA government had failed not only on the economic front but also on external and internal security as well as diplomacy.
"This government is suffering from policy paralysis and looks helpless and depressed in the absence of any vision and conviction," the BJP president claimed.
He said his party had played role of the principal opposition with responsibility "as expected of us by the people", and asked in a sarcastic poser: "Does Prime Minister expect BJP to be a cheer leader in the Parliament?"
Rajnath said no Prime Minister in the world would have blamed the opposition for the country's state of economy.
India was witnessing a "1962 like situation" with China and Pakistan being "all weather friends" encircling the country and the government failing to react strongly and effectively to protect strategic interests, he said.
On the controversy surrounding the Tulsi Prajapati fake encounter case and role of Modi, Rajnath said, "At present, I have no information on this."
Congress on Tuesday demanded the resignation of Modi in the wake of a sting operation claiming to "expose" a plan by senior BJP leaders to save the Gujarat Chief Minister's key aide Amit Shah in Tulsi Prajapati fake encounter case.
"It is Congress which presents a divided house and not BJP, which has never seen a vertical split," Rajnath told reporters.