The Irish building materials group, CRH is set to pick up a controlling 51 per cent stake in the cement operations of Jaiprakash Associates in Gujarat for an enterprise value of Rs 4,200 crore, according to people familiar with the developments.The Irish company will also have the option of increasing its holding to 65 per cent over the next three years at a pre-fixed price via a call option. CRH will have the option of picking up an additional 14 per cent from Jaiprakash Associates at the current price plus a 16 per cent annualised return or at a fair price determined by an independent valuer, whichever is higher, said one of the officials familiar with the ongoing negotiations.Jaypee Cement Corporation has two plants in Gujarat in Sewagram and Wanakbori – each having a capacity of 2.4 million tonne (mt). After the transaction, Jaypee Associates, the diversified power to real estate and cement group’s flagship, will be able to deleverage its balance sheet, which has been struggling to bring down its consolidated debt of Rs 45,000 crore.