Portuguese economy will decrease 3.1 percent in 2012, the country's central bank said on Tuesday in its winter economic statement.

The forecast shows a darker prospect than originally stated by the bank, the government and most of the international institutions.

When Portugal signed the bailout agreement with the European Union and the International Monetary Fund in April 2011, the forecast was a 2.2 percent contraction in gross domestic product (GDP) this year.

In October, during the parliament discussion of the budget for 2012, the prediction was a 2.8 percent fall, while the European Commission said that the economy will shrink by 3 percent.

The central bank ascribes the worsening of the estimates mainly to a 6 percent reduction of the internal demand, and the new consolidation measures that the government will have to implement due to an unfavorable international financial situation.

The bright spot in the forecast is that the Portuguese exports will grow by 4.1 percent. This figure is lower than the 4.8 percent originally expected, but it is considered a good sign in the light of the recession in Spain, the country's most important market, which buys 25 percent of Portuguese exports.