Bulgaria is not prepared yet to adopt the euro, but membership in the common currency zone is its future, President Rosen Plevneliev said in an interview for Die Welt.

"We are not 100 % ready, but the country is one of only three European countries, which completely fulfill the Maastricht criteria," President Rosen Plevneliev told the German newspaper.

The euro must survive and the expansion of democracy in eastern Europe must continue, the newspaper cited Plevneliev as saying.

According to Plevneliev the "right recipe" for Europe is a mix of fiscal discipline and structural reforms for more competitiveness and growth..

Earlier in the week analysts also toned down Bulgaria's government enthusiasm for adopting the common European currency, saying it makes more sense for the country to take its time.

Fiscal discipline is especially important for Bulgaria, as a large budget deficit may put pressure on the economy's currency board, which pegs the Bulgarian lev to the euro.

The currency board has been in place since an economic crisis in 1997 led to hyperinflation and the lev's collapse.