(Updates with Commission draft, background)
By Marcin Grajewski and Martin Santa
BRUSSELS/BRATISLAVA, April 29 (Reuters) - The European Commission will give Slovakia the green light next week to join the euro zone on Jan. 1, 2009, a draft proposal from the European Union's executive arm showed on Tuesday.
If backed by EU finance ministers as expected, the recommendation will clear the way for the ex-communist country of 5.4 million people to exchange its crown <EURSKK=> for the currency now shared by 15 nations.
"Slovakia fulfills the necessary conditions for the adoption of the single currency," the Commission's document, obtained by Reuters, said.
The recommendation is set to be backed by the whole European Commission on May 7 and passed on for approval in June by European Union finance ministers, probably a formality.
The European Central Bank will make a separate recommendation.
The Commission draft, drawn up by European Economic and Monetary Affairs Commissioner Joaquin Almunia and discussed by senior officials on Tuesday, said Slovakia met all euro zone entry criteria on inflation, interest rates, budget deficit, public debt and currency stability.
Slovakia joined the EU in 2004, along with nine other, mostly ex-communist countries from central and eastern Europe.
EU newcomer Slovenia adopted the euro on Jan. 1, 2007, with Cyprus and Malta following suit this year.
Other EU new members -- the Czech Republic, Hungary, Poland, Estonia, Latvia, Lithuania, Bulgaria and Romania -- are expected to adopt the currency only after 2010.
The Commission will say on May 7 those countries are not ready for the euro either because of their high inflation or wide budget deficits or because they have not yet joined the ERM II currency grid, a proving ground for the euro.
Old EU members Britain, Denmark and Sweden have opted to stay outside the euro zone.
INFLATION HURDLE
Joining the euro will crown Slovakia's ambitious economic reforms launched by the previous right-wing government that have turned the country, once burdened by inefficient Soviet-era industries, into an investor darling and a major car producer.
The biggest hurdle on Slovakia's euro path was meeting the inflation criterion in a sustainable way, a tough job for a country that had double-digit economic growth last year.
A country wanting to join the euro must have inflation no higher than 1.5 percentage points above the average of the three EU members with the lowest inflation rates.
The Commission draft confirmed Slovakia's 12-month average inflation was 2.2 percent in March, comfortably below the permitted ceiling of 3.2 percent.
"The average inflation rate in Slovakia ... is likely to remain below the reference value in the months ahead, albeit with a narrowing margin," it said.
Slovak left-wing Prime Minister Robert Fico has worked hard to convince the Commission about his determination in fighting inflation. In April, the government passed a fiscal package aimed at quicker budget deficit reduction.
The EU's 27 ministers will in early July set the final exchange rate between the crown and euro.
Fico has said he will aim for the strongest possible switchover exchange rate. The market so far expects a rate of 32.50, according to a Reuters poll, compared with its all-time high of 32.200 reached on Monday.
The Slovak central bank left its main interest rate unchanged on Tuesday at 4.25 percent, 25 basis points above the euro zone equivalent. (Editing by Dale Hudson)