Mumbai, Dec 22 :     The Tatas today sold half of their 14.4 per cent holding in Associated Cement Companies (ACC) to a Gujarat Ambuja Cement (GACL) subsidiary in a Rs 455.10-crore deal that signals a gradual departure of India?s first business family from the company and narrows the lead in the race for market supremacy. Ambuja Cement Holdings, a wholly owned subsidiary of Gujarat Ambuja, acquired 1.23 crore shares in spot deals at a price of Rs 370 on Tuesday while the Tatas indicated that they ?retained the option to sell the remaining 7.2 per cent stake in future?. The ACC board met today and invited Ambuja Cement managing director Narotam Sekhsaria to join as a director. The markets applauded the deal by pushing up the ACC scrip by Rs 19 to Rs 260 on the BSE while Gujarat Ambuja closed at Rs 360.70 in a gain of Rs 26.70; both stocks hit the upper-end circuit filters. Brokers added that with Ambuja Cement picking up a stake in ACC, the valuations of both the companies would improve drastically. The stake sale, which comes after Tatas? attempts to hike their holding in the premier cement company was stonewalled by financial institutions, has fuelled expectations of a consolidation in the cement industry. The two companies will have a combined capacity of 21 million tonnes. After the aborted preferential issue, which would have pushed up their holding to 20 per cent, the Tatas were considering their future role in the cement company as part of a group restructuring exercise. The main concern was to protect the interest of various Tata group firms which hold a stake in ACC. The Tatas, in a veiled hint at the preference issue, said they were taking a relook at their role after their efforts to ?strengthen and support? ACC did not succeed. ?Since our objective to strengthen and support the company was not met, we were having a re-look on our future role in ACC,? a Tata press release said. The group clarified that the preferential share issue route was taken since that would have provided ACC with the much-needed equity finds unlike an open offer under which the money would not have benefited the company. ?The management of ACC is not proposed to be distributed,? the Tatas said categorically. A Tata release said the decision to divest a part of their shareholding in ACC to Gujarat Ambuja would enable the two firms pool their strengths. Senior Ambuja Cement officials said it was ?too early? to say whether their company would raise its holding in ACC further. They also said cash flows at the disposal of the company ? pegged at Rs 350 crore ? was more than adequate to fund acquisitions. GACL had, only last week, acquired DLF Cement for Rs 349 crore. Ambuja Cement, known to be one of the low-cost cement firms, produced 7 million tonnes in the previous financial year. While its capacity is expected to rise to 9 million tonnes this year, the company has charted plans to increase the output to 15.5 million tonnes over the next three years. ACC, on the other hand, had embarked on a Rs 750-crore modernisation/expansion programme targeted at its existing plants. The efforts were part of a larger plan to achieve an annual capacity addition of 3 million tonnes by mid-2001. The company had launched a 1:4 rights issue at a premium of Rs 45 per share in July to part-finance its expansion programme. Analysts say the alliance will make Gujarat Ambuja a cement powerhouse with a strong country-wide presence. The company, strong in the north and the east, can now tap the southern region where some of ACC?s plants are located. ?They will fight Madras and India Cements on the southern turf. The equity alliance will help GACL spread its wings across the country and give it more strength,? Khandwala Securities analyst Shashank Choudhary said.