It said in a statement that the government has imposed a special tax of eight rupees per kilogramme and 100 rupees for a 12.
5 kilo domestic gas cylinder from December 31, 2008.
The new tax came a day after the government said the price of a 12.5 kilo Shell gas cylinder would be reduced by 166 rupees as it announced a wide-ranging 'stimulus package' to boost economic growth.
Government officials said import taxes would be raised as global commodity prices fell to collect funds to fund the stimulus package.
On November 20, 2008 the government increased the customs duty on imported petrol by 10 rupees when global energy prices started to dive.
The Shell Gas Lanka statement said it cannot buy LPG made by the state-owned Ceylon Petroleum Corporation.
As a result, the company said all Shell Gas supplies for domestic LPG users are imported.
"Because of this Shell gas price is more than that of suppliers who get locally made supplies," the statement said.
"If Shell Gas Lan