Bhubaneshwar: Thousands of people demonstrated in eastern India on Tuesday against South Korean firm Posco's plans to build a steel plant, the first major protest since the Supreme Court gave the project the go-ahead.

The villagers, many of them carrying bows, arrows and sticks, walked to the district of Jagatsinghpur in Orissa, where the plant will be based, shouting slogans against Posco.

In a ruling last month, India's Supreme Court allowed Posco to use large swathes of forest land to build a $12 billion plant, the largest foreign direct investment project in the country.

Villagers in Orissa say the Posco plant will force them off their farmland and could displace about 20,000 people. Posco and the government say the plant will create jobs in the impoverished state.

"We will not give an inch of land from our area to the plant," Prasant Paikray, a protest leader, told Reuters. "We assembled here to threaten the government and the company not to send any officials for land survey or for land possession."

The rally against the Posco plant mirrors similar protests in Singur, West Bengal, where demonstrators have slowed work at a Tata Motors car factory.