The European Union's biggest ever enlargement passed its crucial first popular test yesterday when voters in Malta, the union's smallest newcomer, said a narrow Yes to membership.  Final returns showed 53.6% of voters in the tiny Mediterranean island had opted to join the EU, quashing fears that a No might trigger a domino effect among millions of east Europeans who will make the same decision over the coming months.  Eddie Fenech-Adami, the prime minister and leader of the ruling nationalist party, claimed victory and his deputy, Lawrence Gonzi, said: "The electorate has given a clear-cut indication that it wanted the country to join Europe."  But the membership issue could be challenged in a new general election as soon as next month. Romano Prodi, the president of the European commission, said: "This is a historic choice which will have a lasting impact for the future of Malta for generations to come. This is a choice for stability and growth, as well as for the peaceful reunification of Europe and the European people."  Triumphant Yes campaigners led honking motorcades through the streets of Valletta and waved blue and yellow-starred EU flags alongside red and white Maltese ones as the results were announced. One slogan read: "Vote Yes, for us, for our children, for our country."  Mr Fenech-Adami had called for a national, not a party-political decision, arguing that it was common sense for the island's 380,000 people to join the world's most powerful economic bloc.  The No camp, led by the opposition Labour party and the largest trade union, proposed a "partnership" with the EU but failed to explain how their "Mediterranean Switzerland" would actually work.  Alfred Sant, the Labour leader, demonstratively failed to vote on Saturday, having argued that the issue should be tested in a general election, not a referendum. He had urged supporters to stay away, vote No or spoil their ballots by writing "Viva Malta".  But Mr Fenech-Adami is now expected to call an early election to consolidate his victory, probably in April, just before all 10 candidate countries sign their accession treaties at a grand ceremony at the Acropolis in Athens.  Malta's vote was the first in a series of polls over the next few months which will seal the expansion of the union, from the current 15 to 25 members in May 2004.  Slovenia and Hungary are next, with the final membership referendum due in Latvia in September. Most attention is likely to focus on Poland, the largest country in the new intake, when it votes in June.  EU officials had been nervous about the outcome in Malta, a former British colony, because it is the only candidate country in which the main opposition party opposes membership.  Malta had to overcome a tradition of political isolation and economic protectionism which will be replaced by the stringent but potentially rewarding requirements of EU membership. When it joins, it will have one commissioner in Brussels, a proportionate number of members of the European parliament, and votes in the council of ministers. Maltese will become an official EU language.  In a country where the conduct of politics is intense and often highly personalised, the campaign was acrimonious. Labour was accused of scaremongering when it warned of job losses, price rises and an influx of foreigners.  But at last December's Copenhagen summit, Malta won generous membership terms and long transition periods before it must comply with all aspects of EU legislation on issues ranging from food safety to financial services.  Maltese divided into those who feared that staying out of the EU would leave them an isolated backwater, and those who were who were worried about national sovereignty.  The government made a strong economic case, arguing that EU membership would be a boost for a country which relies heavily on services, tourism and shipping. "This will bring investment to our economy and create jobs," Mr Fenech-Adami said.  In the final days of the campaign there was a whiff of panic from the No camp, which was widely perceived as exaggerating or lying.  Eurosceptics from Britain and elsewhere pitched in to play on fears about domination by Brussels, abortion and neutrality - issues which had also featured in the referendums in Denmark on the euro, and Ireland's on the Nice treaty.  More at guardian.co.uk/eu Classification Language: ENGLISH Subject: EUROPEAN UNION (90%); ELECTIONS (89%); REFERENDUMS (89%); EUROPEAN UNION ACCESSION (89%); VOTERS & VOTING (89%); CAMPAIGNS & ELECTIONS (89%); EUROPEAN UNION INSTITUTIONS (89%); POLITICS (89%); INTERNATIONAL ECONOMIC ORGANIZATIONS (89%); UK GENERAL ELECTIONS (88%); POLITICAL PARTIES (78%); LABOR UNIONS (78%); PRIME MINISTERS (75%); HEADS OF STATE & GOVERNMENT (75%); SEPARATISM & SECESSION (70%) Company: EUROPEAN UNION LEISURE LTD (96%); EUROPEAN UNION LEISURE LTD (96%); EUROPEAN UNION (91%); EUROPEAN UNION (91%); EUROPEAN COMMISSION (56%); EUROPEAN COMMISSION (56%) Organization: EUROPEAN UNION (91%); EUROPEAN UNION (91%); EUROPEAN COMMISSION (56%); EUROPEAN COMMISSION (56%); EUROPEAN UNION (91%); EUROPEAN UNION (91%); EUROPEAN COMMISSION (56%); EUROPEAN COMMISSION (56%) Person: ROMANO PRODI (55%) Geographic: ATHENS, GREECE (79%); VALLETTA, MALTA (79%); MALTA (94%); EUROPE (94%); EUROPEAN UNION MEMBER STATES (94%); SLOVENIA (79%); POLAND (79%); SWITZERLAND (79%); UNITED KINGDOM (79%); HUNGARY (79%); LATVIA (58%); EASTERN EUROPE (58%)