However, further revision of taxes was not possible considering the financial constrains, he said.
'In the present situation where there are lesser avenues of revenue-generation for state governments, further cut on taxes will affect their economic condition,' he said.
He recalled his recent statement ruling out increase in bus fares and said it would cause a loss of Rs 150 crore.
With a tax rate of 30 per cent on petrol and 21.43 per cent on diesel, the state had one of the lowest tax rates, he said.
It was at the behest of DMK and some other partners of UPA that the government had not increased the prices to its desired levels, he claimed.
On the issue of swine flu with fresh cases being reported in the state, Karunanidhi said the Health department had been directed to act swiftly and preventive measures were put in place when the virus was spreading in Kerala.