Croatia has joined the EU as the 28th member, with an official ceremony having been held in the capital Zagreb, last night.

Fireworks lit the sky, Zagreb's mediaeval cannon fired and a choir sang Beethoven's Ode to Joy as two men clad in white abseiled from a nearby building to bring the EU's yellow-starred blue flag to the central Ban Jelacic square, packed with around 20,000 cheering Croatians.

The ceremony represented a milestone in Croatia's recovery from a 1991-95 war to secure independence from Yugoslavia. But it was held against a backdrop of economic woes in the Adriatic republic and the bloc it is joining.

Irish deputy Prime Minister Eamon Gilmore welcomed Croatians into the EU on behalf on the ending Irish EU presidency, while Lithuanian Prime Minister Dalia Grybauskaite said her welcome in Croatian on behalf of the Lithuanian presidency which starts on July 1.

The country of 4.4 million people becomes only the second of the seven states carved from federal Yugoslavia to enter the EU, following Slovenia in 2004.

Croatia's accession marks the first expansion of the EU eastwards since 2007, when Romania and Bulgaria joined, and the "Big Bang" enlargement of 2004 when 10 new members came aboard.