Foreign exchange fluctuation

Dear All,

One of my clients have purchased spare parts for the machinery by paying 100% advance for the same.

The bill is booked subsequently by using the exchange rate of the day when the goods are received. The difference in the payment and booking is treated as Forex Loss.

My query is shld the Client book the bill at the rate of payment i.e. which does not result in forex fluctuation, since the outflow have been fixed.

Please reply in reference to AS 11.

Will be helpful if proper 'paras' are qouted.

Thanks  Regards