The West Bengal government is yet to sign the lease agreement with Tata Motors for the land given to it at Singur for the small car project, with the company beginning its construction work."The lease agreement was initially scheduled to be signed in January, but it could not be done as the Tata Motors officials could not give time. The date for signing is yet to be finalised," Industry Secretary Sabyasachi Sen said today.He said Tata Motors was, however, allowed to start construction work at the Singur site because the company had a deadline for rolling out its small car.The government would have to give various incentives to the Tatas to wean them away from states like Uttaranchal in setting up their small car project in West Bengal, he said, adding that the incentives, however, were being negotiated.Meanwhile, work went on at the Singur site for the second day and construction equipment and earthmovers began rolling in.