Treatment of advance paid to capital goods vendor

Dear Experts

Could anyone gude me on the following query

What is the accounting treatment of sums paid to foreign capital goods vendor under milestone payments method for supply of certain capital goods?. Since the transaction has taken place long time, the same has been accounted in advance at the time of remttence. Can it be treated as work in progress now or still to be kept under capital advance? 

Could you please clarify asap.

Thanks in advance

Best regards..Jagadeesh