"Congress party's doors are open for everyone," he told reporters when asked if he would welcome Sidhu to the Congress fold.
He, however, said there was no communication between him and Sidhu so far. Asked if any Congress leader was in touch with Sidhu, he said, "Not to my knowledge".
Amarinder said Sidhu, who hails from Patiala, had a Congress background as his father late Bhagwant Singh Sidhu had been an office bearer of District Congress Committee.
When asked if he had met Sidhu in the recent past, Amarinder said, "We are both from Patiala and we are both Sidhus. I don't remember having met him for a long time now."
More From This Section
On whether Congress would invite the former Amritsar MP to join the party, the PCC chief said, "He is yet to resign from the BJP".
In a jolt to BJP ahead of Punjab elections, Sidhu had yesterday resigned his Rajya Sabha membership, saying "the burden is over".
Sidhu today kept himself away from the media while his wife Navjot Kaur, a BJP MLA, did all the talking, saying his resignation from the Rajya Sabha yesterday meant he has also quit the party and the only option for them now was to join the AAP.