provide bitumen to the petitioner at the P.W.D.Schedule of rates, the petitioner incurred additional amount of Rs.2,99,105.43. The petitioner submits that immediately on purchasing bitumen from K.R.L. he sent Ext.P9 letter dated 2.4.2004 to the respondents requesting for immediate steps to pay the differential cost of the bitumen. In the meantime the work was completed and Ext.P10 bill was prepared by the 2nd respondent. On 20.1.2005 the petitioner has given payment also. But the bill does not include the differential cost of bitumen claimed by the petitioner. On learning that only schedule rate is taken as the basis of Ext.P10 the petitioner submitted Ext.P11 letter dated 5.2.2005 claiming payment of a total amount of Rs.3,27,006.43 which takes in differential cost and transportation charges amounting to Rs.27,999/-. Referring to Rule 18 of the Kerala Panchayat Raj (Execution of Public Works) Rules, 1997 the petitioner submits that unless otherwise expressly provided in those Rules, rules and methods adopted in the P.W.D. regarding payment for contract works are to be followed in Panchayats also. The petitioner refers to G.O.(P) NO.84/97/PW&T dated 19.8.1997 and submits that the contractors of P.W.D. who purchases bitumen from the open market are entitled for the differential costs. Ext.P12 is copy of that Government Order. The