"BJP had earlier launched a drive to collect bricks and sought donations for the construction of Ram temple at Ayodhya, but later sold them. Now they will collect iron pieces from across the country and sell it too," Singh told reporters.
He said that Sardar Patel had banned the RSS after the assassination of Mahatma Gandhi, "even as the BJP has launched a drive to collect iron in his name".
The Congress leader also raised question over the sequence of happenings in BJP, including Modi's appointment as campaign committee chief and veteran BJP leader L K Advani's resignation.
"I am not able to understand how the same persons suddenly became social workers in the eyes of Advani, whom he had earlier accused of indulging in fulfilling their own vested interests," Singh said.
He also blamed the BJP for creating hurdles in the passage of important bills of public interest in Parliament.