Malta on Saturday savoured its first day as a member of the European Union after a spectacular midnight welcome in the capital Valletta, but many feel the adjustment to the EU's club of 25 will batter its fragile island economy.

The country's main newspapers marked the occasion with special editions, and their front pages basked in the aftermath of the celebrations.

"Ode to Europe", said the Times of Malta over a photograph of the spectacular celebrations.

"Inside the European Union, the island stands a better chance of meeting existing and new challenges in development than if it were to stay out of the community," it said in an editorial, urging the population to "seize the moment" and overcome petty political squabbles at home.

Writing in a special supplement, the opposition Labour Party leader Alfred Sant warned that many EU regulations would create problems for Malta as they are implemented "not least because they were not designed to fit the context of a micro society living on a very small peripheral island."

Sant, who had campaigned hard for rejection of EU membership in a close-run referendum last year, said Labour accepted the result but forecast "a period of disillusionment" ahead for the Maltese.

The Maltese language pro-government newspaper "In-Nazzjon" headlined: "Today we are In".

"Let's celebrate the greatest day in our history as a sovereign country," the newspaper said in an editorial.

Malta's Archbishop Joseph Mercieca emphasised the island's deep-rooted Christianity during a special mass to celebrate EU accession attended by President Eddie Fenech Adami and members of the conservative government.

"Malta in Europe should not consider only material benefits, it should also take into account its Christian roots of our country and Europe," the archbishop said in his homily during mass at the 16th-century St John's Cathedral.

"Through its words and deeds it should assist so that the community of people in the EU understand and feel the need of God and religion. There is no other way if we want to encourage the full development of the person."

Overwhelmingly Roman Catholic Malta insisted on maintaining its ban on abortion in hard-fought accession negotiations.

More immediate concerns are being focused on the economy and growing joblessness after the Mediterranean island chain overhauled its legislation and economy to enter the EU.

Local food processing companies have complained of higher costs now that they have to source raw materials like sugar and flour in the European Union instead of the cheaper open market, according to Malta's Chamber of Small and Medium-sized Enterprises.

For now, however, the emphasis is on the opportunities membership will bring for its insular economy.

In its editorial, the Times said EU membership was the most important day in the history of the tiny island nation, after its independence from British rule in 1964, and the withdrawal of British forces stationed on the island in 1979, an event which is now marked by Freedom Day.

"These and all the social and economic development that the country has had since then, have fashioned a new Malta."