The party also sought a time-bound CBI probe into the matter and expressed its surprise over the "silence" of Congress chief Sonia Gandhi and vice president Rahul Gandhi, calling their conduct "shameful".
"BJP's stand on corruption is of zero tolerance while Congress not only encourages corruption but also protects the corrupt... After the recent revelation, Chandy has lost moral right to remain chief minister. He should immidiately resign," BJP secretary Shrikant Sharma said in a statement.
He said the silence was raising many questions and wondered if top Congress leaders had a share in the "scams" of Chandy, Singh and other leaders who, he alleged, also included Uttarakhand Chief Minister Harish Rawat and former Union minister Preneet Kaur.
"People want to know what is your compulsion that you cannot act against your three chief ministers facing corruption charges," he said.
Himachal and Uttarakhand CMs have denied the allegations against them even as Preneet Kaur today said that neither she nor her son Raninder Singh has received any notice regarding alleged bank account in HSBC.