Finance Minister P Chidambaram today invited 582 top corporates to avail of a single-window tax payment facility, and promised to set up a national tax tribunal (NTT) next year to cut disputes and improve collections."Taxes must be paid. I don't believe in blunt measures like search and seizures. Sometimes, we have to use blunt instruments," he said after flagging off the roadshow for large taxpayers units (LTUs) today.Corporates can confrim their participation in LTUs before January 10 so that the tax departments could assess the taxes from next fiscal. "I promise you that LTUs will be modern offices and assessment and payment will be through electronic media. Senior officials will assist you," Chidambaram said."LTUs will give an opportunity to taxpayers and collectors to discharge obligation in a hassle-free and dispute-free manner. The cost of compliance will also come down," he added.The facility of filing excise, corporate tax and service tax under one roof would be "optional" for companies paying excise of over Rs 5 crore and assessed by income tax in any of the five cities - Delhi, Mumbai, Chennai, Bangalore and Kolkata - where LTUs would be set up to facilitate payments.