Former Punjab Chief Minister Captain Amarinder Singh met National Security Advisor (NSA) Ajit Doval at his residence on Thursday.

Singh had on Wednesday met Union Home Minister Amit Shah to discuss the ongoing farmers' agitation and urged him to resolve the crisis by immediately repealing the three farm laws.

The meeting came amid fresh turmoil in Punjab Congress with the sudden resignation of state Congress chief Navjot Singh Sidhu and led to speculation that the Congress leader may be warming up to the BJP.

Amarinder Singh had resigned as Chief Minister on September 18 and had told the media that the Congress leadership had let him down. He had also taken a dig at Sidhu over his resignation, saying he is not a stable man.

The meeting took place amid efforts of the Bharatiya Janata Party (BJP) to ensure a contest in the forthcoming assembly polls in Punjab.

The BJP faces a formidable political challenge in the state from ruling Congress, Aam Aadmi Party (AAP) and SAD-BSP combine.

Shiromani Akali Dal was a trusted partner of BJP in Punjab but parted ways over its stance on the farm laws.

If Amarinder Singh joins the BJP, the political equations in the state will change and will give the party an advantage in assembly polls.

From being seen as a "non-contender" in the power equations, the BJP is looking to emerge as a formidable contestant in Punjab assembly polls.