Tds on professional fees to foreign company

DEAR SIR, AN INDIAN COMPANY WANTS TO MAKE PAYMENT OF RS. 10 LAKHS FOR PROFESSIONAL FEES TO A FOREIGN COMPANY ( UK) WHO DOES NOT HAVE PAN NUMBER IN INDIA. IS TDS TO BE DEDUCTED AT 20.6% AS PAN IS NOT THERE OR AT SOME OTHER RATE. ALSO WHAT IS THE RATE OF DTAA, I UNDERSTAND THAT IT IS 15 % IF PAN IS THERE, WHAT IF PAN IS NOT THERE ? ALSO HOW TO ISSUE TDS CERTIFICATE AND FILE ETDS RETURN WITHOUT PAN NUMBER ? PLEASE ADVISE RAJESH PODDAR