The process of valuation of the Ambani business empire is likely to be completed within the next three weeks, which could lay the basis for a blueprint to end the family feud that has hurt the Reliance group, sources familiar with the exercise said today.K V Kamath, CEO of ICICI Bank and a friend of the Ambanis, is doing the valuation following a family conclave in Mumbai on December 28 at which the feuding brothers - RIL chairman Mukesh Ambani and vice-chairman Anil Ambani - were present along with their mother Kokilaben and their two sisters Dipti and Neena.Sources close to the Anil camp said that it was agreed at the meeting that Kamath would undertake the valuation of the Reliance group estimated to be worth between Rs 90,000 crore and Rs 1,00,000 crore. Thereafter, a formula for "legal split" between the brothers would be worked out.According to sources, the understanding at the December 28 meeting was that valuation would be completed by the end of January, "give or take a few days". Thereafter, the family would get together to discuss the roadmap for the split.The key to efforts of Kamath, whom both the brothers have met separately more than once since he began the exercise, lay in his valuation and whether any formulae emerge thereafter that are acceptable to all the concerned.The deliberations of the December 28 meetings may have been minuted, sources indicated, emphasising that everyone ought to honour the understanding.