The stock of Jet Airways, which has been on the rise on hopes that the Centre will clear its deal with Etihad, may lose momentum. This is because the proposal of the Abu Dhabi-based Etihad Airways to acquire a 24 per cent stake in Jet Airways failed to get the approval of the Foreign Investment Promotion Board last week. The Jet-Etihad proposal has been deferred as the Government sought more details of effective control and ownership. Etihad, which acquired a 24 per cent stake in Jet Airways for over Rs 2,000 crore in April, may now have to re-work the ownership structure proposed in the deal.