Tens of thousands of people took to the streets across Europe today as part of the annual May Day rallies.

The demonstrations were given added impetus due to a growing backlash against austerity policies and the continuing eurozone debt crisis.

In Greece, 18,000 people joined demonstrations organised by the main unions against salary and pension cuts.

Spain's largest unions are protesting against recent austerity measures to help the country meet its deficit targets.

Coming in advance of key elections in Greece and in France, demonstrations reflect growing anger against the austerity policies which some eurozone governments insist are necessary to reduce both deficits and Europe's spiralling debt problem.

Unions have also mobilised demonstrators in Italy, Poland, Spain and Portugal.

At a rally in Paris, the leader of the far right national front, Marine Le Pen, said she would cast a blank ballot in the second round of the presidential election, pointedly refusing to support the incumbent President Sarkozy, who badly needs far right votes to win.

Unions in Spain called for demonstrations in 80 cities across the country.

While the need for economic growth over austerity has gained traction across Europe, there remains little consensus about how it should be generated without pushing European debt levels up further.

German union leaders urged May Day demonstrators to fight for big pay rises after a decade of restraint.

The head of the powerful IG-Metall union, demanding a 6.5% rise, described an offer of 3% over 14 months as a farce.

From Hamburg in the north to Stuttgart in the south, the mood of members rallying in sunny weather under red union flags, banging drums and blowing whistles, was combative.

In Berlin, thousands marched through the government quarter to hear speeches at the central Brandenburg gate near the Reichstag parliament building.

President of the Dublin Council of Trade Unions Phil McFadden said that around 500 people took part in a protest in Dublin city centre this evening.