EU economy commissioner Olli Rehn has said that Bulgaria may have its national statistics examined under new EU audit powers.
Speaking to the press at a meeting of EU finance ministers, he expressed concerns over the country's data.
Ministers have agreed to give the European statistical office new powers to make sure EU governments comply with limits on their borrowing.
Misreporting by the Greek government contributed to the current crisis.
"We have had some concerns as regards the statistical performance of Bulgaria and are considering sending a mission shortly ... which has all these audit powers," said commissioner Olli Rehn.
Echoes of Greece
The Greek debt crisis highlighted the problems that European authorities had with verifying economic data given to it by member states.
Like Greece, Bulgaria had to significantly revise its budget deficit calculation for 2009, from 1.9% of GDP to 3.7%.
The Balkan country, which only joined the EU in 2007, was also forced to put plans to join the euro on hold.
Brussels previously cut aid to Bulgaria by 220m euros in 2008 because of concerns over corruption.
However, Bulgaria has fixed its exchange rate to the euro since the euro's inception in 1999.
This means that, as with eurozone member Greece, the Bulgarians cannot easily devalue their currency in order to help their economy.
Mr Rehn's comments about Bulgaria came halfway through a two-day EU finance ministers meeting in Luxembourg to discuss a package of fiscal reforms.
Ministers moved towards an agreement to allow other governments to study their annual budgets before they are seen by national parliaments.
It is a move that the UK government strongly opposes, although officals said a compromise had been found.
French Finance Minister Christine Lagarde said that the idea was not for the actual budget details to be seen by other governments, rather the broader economic targets.
It was a message echoed by commissioner Rehn. He told reporters that governments would not go through each others' budgets "line by line" or get into "bureaucratic nittygritty".
"What interests us is the broad budgetary guidelines," he said.
"It is just a matter of the rules already agreed in the Stability and Growth pact."
Mr Rehn also indicated that all 27 EU governments may adopt fiscal austerity programmes by next year.
"The economic recovery is on a stronger footing and will gain stronger momentum towards the end of this year," he said.
"It makes sense that ... all the member states will start fiscal consolidation at the latest next year, 2011."
However, an agreement to carry out simultaneous budget cuts across the EU may not be welcomed elsewhere in the world.
Over the weekend, US Treasury Secretary Tim Geithner called on countries running trade surpluses - which includes Germany - to increase their spending.
He believes this is necessary to help maintain the global economic recovery.
And some economists say that more spending by Germany is needed to counterbalance necessary spending cuts by countries with large budget deficits like Greece and Spain.
Yet Germany announced on Monday that it intended to carry out a record 80bn euro austerity package.
Mr Rehn defended Berlin, saying the measures are needed to bring Germany's deficit back down to a common EU target of 3% of GDP by 2013.
"I do not call these measures austerity," he said. "I call it fiscal responsibility."
Late on Monday, finance ministers also gave the official go-ahead to a 440bn-euro ($536bn; £363bn) fund - officially called the Special Purpose Vehicle (SPV) - that will be in place by the end of the month.
It will enable the 16 nations that use the single currency to access cheap emergency loans and loan guarantees, should they find themselves unable to raise money on the open market to pay their debts.
Member states hope it will never be needed, but that its existence will convince markets that default fears are unfounded.
In addition to the SPV, the European Commission is making 60bn euros available "to cover urgent financial needs, were it to arise", while the International Monetary Fund will provide another 250bn euros.
The two-day meeting of EU finance ministers also approved Estonia's adoption of the euro from January of next year.
This will make Estonia the 17th country to use the single currency.
Decisions made by the finance ministers will still need to be finally agreed at a meeting of EU leaders in Brussels on 17 June.