Mumbai: Reliance Industries lost its position of the country's most valued company to Tata group firm TCS on Friday afternoon, as the shares of billionaire Mukesh Ambani-led corporate giant fell sharply in a weak market.

At 1450 hours, Reliance Industries (RIL) commanded a market value of Rs 2,27,083 crore, a shade below Tata Consultancy Services' Rs 2,28,153 crore.

RIL has been the country's most valued company for many years, except for a brief period in August this year, when it first lost its top slot to Coal India Ltd, then regained it and was again overtaken by another state-run firm ONGC.

While RIL shares were down 2.72 per cent to Rs 693.50, its lowest level in more than a year, TCS was trading with a modest gain of 0.03 per cent at Rs 1165.70. The benchmark Sensex was 93.57 points down at 15,450.36 at that time.

The marketmen were keeping an eye on the two stocks to know whether TCS would be able to retain its lead till the end of the trade on Friday, which incidentally happens to be the last trading session of the year 2011.

Earlier this month, RIL also lost its tag of the country's most influential stock to another IT firm Infosys, as measured by their weightage on the stock market barometer Sensex. RIL first slipped below Infosys in terms of Sensex weightage on December 12, and thereafter, a situation similar to game of musical chairs has been on display between the two, as they have overtaken each other on various occasions.

Currently, Infosys commands a higher weight than RIL.

Earlier on August 17, Coal India had toppled RIL as the country's most valued company, while the polyster-to-energy- retail conglomerate had slipped to third position below ONGC two days later on August 19.

About a week later, RIL had regained its top slot on August 23, while CIL had slipped to third position. But, ONGC rose to the top slot on August 26, pushing RIL to second position. A few days later, RIL again rose to the pole position on August 29, and had mostly remained there since then.

ONGC is currently ranked third with a market cap of Rs 2,19,362 crore, while CIL is fourth at Rs 1,90,659 crore.