The European Commission has announced that Romania and Bulgaria will be admitted to the European Union in January 2007, but under strict conditions. Commission President Jose Manuel Barroso said both countries had made enough progress to join the union.
Bulgaria's PM compared the move as the fall of the Berlin Wall for his nation.
However, both countries will undergo scrutiny for progress in curbing organised crime and corruption, as well as ensuring food safety and the proper use of EU funds.
The conditions are significantly tougher than those imposed on previous new members (namely, the East European EU-25 accession States from the former Soviet Union in May, 2004).
The BBC's Oana Lungescu in Strasbourg says they are intended both as a reassurance for EU citizens, approximately half of whom support further enlargement, and as a warning to Turkey and the Balkan nations still lobbying for EU membership for 2010.
The commission's report confirms that after seven years of talks, Bulgaria and Romania are able to take on the rights and obligations of EU membership. Reading the report, Mr Barroso said the two nations' entry would be a "historic achievement".
"Bulgaria and Romania have carried out an extraordinary reform process and they have gone through a remarkable transformation," he said. The two countries missed out on the EU's big eastward expansion in 2004.
"This is the genuine and final fall of the Berlin Wall for Bulgaria," Bulgarian Prime Minister Sergei Stanishev is quoted as saying.
However, the commission president cautioned that there were a number of areas where further progress was needed in the months leading to accession and beyond. Unless Bulgaria cracks down on organised crime, legal decisions taken by its courts could be disregarded in the rest of Europe.
Both countries will have to report every six months on progress in fighting corruption. By March 2007, they also need to set up agencies to handle millions of euros worth of EU farm aid, or risk losing a quarter of the cash.
Both will face food export bans due to outbreaks of animal diseases like swine fever, while Bulgarian planes could be banned from flying into EU airspace until the country improves its air safety standards.
There could also be restrictions on migration to other EU countries for up to three years. An EU official said the commission did not want to punish Bulgaria and Romania, but to make them work harder to carry out reforms.
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