Our co has foreign project where indian sub-contractor's are employed. in making payments to them we are deducting tds from their claims. now we have a centralised PAN but for TAN we have to apply it for project to project basis. so at the time of depositing challan / return filling we have to show our tan in our retun. which tan we have to write down......indian project tan, where from our finance functionis operated for that foreign project or else.