Though he did not clarify whether he would resign from the cabinet or the party. Addressing a poll rally in favour of Congress' Bathinda candidate Amrinder Singh Raja Warring, Sidhu lashed out at the Badal family for allegedly "ruining" Punjab during the previous SAD-BJP regime.
On the last day of poll campaigning, Sidhu addressed several elections rallies in Bathinda, which is considered a stronghold of the Akali Dal.
"I had earlier left Rajya Sabha seat (when he was in the BJP)," Sidhu told the gathering.
He claimed that the BJP in 2014 had asked him to leave the Amritsar seat and contest from other parliamentary constituency.
"If a punishment is not given to the guilty of sacrilege (of religious scriptures) and if Guru does not get respect... Sidhu will resign," said state's tourism and cultural affairs minister.
At a rally in Faridkot on May 15, Congress president Rahul Gandhi had promised strict action against those involved in the desecration of Guru Granth Sahib in 2015.
From Bathinda, Warring is pitted against Union minister and SAD candidate Harsimrat Kaur Badal, Punjab Ekta party chief Sukhpal Singh Khaira and AAP's Baljinder Kaur.