The indefinite siege by West Bengal's opposition Trinamool Congress in front of the Tata Motors small car factory site in Singur on Monday caused a traffic gridlock on the national highway and hampered the movement of vehicles entering the state. 

"There's a huge traffic snarl on NH-2 because of the Trinamool Congress agitation. Several long distance vehicles coming from other states were diverted," Hooghly district police superintendent Rajiv Mishra told IANS. 

He said the entire Durgapur expressway in Hooghly district was clogged due to the siege. 

"Many trucks had to stop before entering the district," Mishra said.

The Trinamool-led Krishijami Jiban Jibika Raksha Committee (KJJRC), which opposed the takeover of farmland for the Tata project, had called for an indefinite protest at the Nano factory site from Sunday. 

The protesters are demanding the return of 400 acres of land which they allege was forcibly taken from "unwilling farmers" to build ancillary industries adjacent to the Tata Motors' main plant. 

A total of 997.11 acres was acquired for the project, of which 691.66 acres belonged to farmers who gave their land willingly.

"We don't accept this claim that the traffic jam was caused because of our political programme. We are constantly allowing all emergency vehicles through the Durgapur expressway. But we would request people to kindly bear with us during this crucial point of our movement," senior Trinamool Congress leader Madan Mitra said.

He said the problem of Singur farmers, whose land was forcibly acquired by the state government, was much more critical than the troubled passengers who were stuck on the way.