Croatian Democratic Union (HDZ) president Tomislav Karamarko told reporters Croatia was no longer in a recession but officially in a depression.
He said the government had discouraged enterprise and destroyed the idea of entrepreneurial capitalism through taxes and gas and electricity prices.
Karamarko said nobody had expected the government to make miracles in its first six months but that it should now think about its responsibility because it had not stopped the negative trends and enabled investments.
Croatian Labour Party president Dragutin Lesar said the GDP decline was the result of the government's conviction that the crisis could be solved only through economies as well as of a restrictive monetary and fiscal policy, reduced purchasing power and no serious investment in production.
Lesar said the fixed exchange rate of the kuna and frequent tax changes had discouraged investment and reinvestment of profit.
Kresimir Bubalo of the Croatian Democratic Alliance of Slavonia and Baranja said the GDP decline was due to lack of measures and frequent changes in strategic guidelines. He said GDP would fall in 2013 as well, also because the government had not negotiated an extension of the agreement with Central European Free Trade Agreement countries.