New Delhi, Aug 13 (IANS): Describing the pro-Khalistan rally in London by the Sikhs as a conspiracy to divide the country, the Congress on Monday questioned the Narendra Modi-led government's silence on it.

"As a sinister conspiracy is hatched to revive militancy in Punjab, why are BJP-Akali Dal mum? Why has the 56' Modi government been stunned into a conspiratorial silence? Isn't it a conspiracy to break the country? Why silence then?" Congress spokesman Pradeep Singh Surjewala said in a tweet attaching a news report about the pro-Khalistan rally.

The Sikhs for Justice (SFJ), a human rights advocacy group with radical leanings, held what it calls a "London Declaration" on an independence referendum for Punjab at Trafalgar Square in London on Sunday.

Thousands of Sikhs and their supporters gathered to demand a 'Referendum 2020' campaign in Punjab.

They also brandished banners reading "Free Punjab, End Indian occupation", "Punjab Referendum 2020 for Khalistan" and "We will re-establish Punjab as an independent country".