Tata Consultancy Services (TCS), India's largest software services exporter, is in final stages of signing a 5-year contract worth about Rs 200 crore with the Income Tax Department to upgrade its IT infrastructure.

The Mumbai-headquartered firm will upgrade department's nation-wide IT infrastructure, which will involve updating the software and the hardware to ensure seamless integration of services and information across all the offices.

"TCS is in final stages of signing the contract with IT Department. It will happen shortly. The project involves upgrading the entire IT network to smoothen the process of sharing information as well as enhance coordination," sources said.

TCS, however, declined to comment on the development.

The IT services firm also signed a contract today with Saudi Arabia's National Commercial Bank to implement a new core banking software platform. The agreement between the two parties will be valid for two years.

Tata group's IT firm has also attained a market valuation of Rs 4 lakh crore -- becoming the second company in Indian markets after Reliance Industries to cross this milestone.

At present, TCS is the only company with a market value of over Rs 4 lakh crore as Reliance Industries had slipped below this below level.