Paris unveiled the latest giant to grace its famous skyline, with the formal inauguration of France’s tallest skyscraper, known as the First Tower.

At 21,000 tonnes, the First is more than twice as heavy as the French capital ’s tallest and most famous landmark, the Eiffel Tower, which nevertheless beats it for sheer height at 324 metres.

The spire was born when developers stripped down and rebuilt the mighty Axa block in La Défense business quarter on the western edge of the city, adding 69 metres to send it soaring to 231 metres.

Now, the tower tops the city ’s previous unloved tallest office block, the slab-like Tour de Montparnasse, which looms over the Left Bank at 210 metres tall.

Compared to major financial centres like London, Frankfurt, New York or Hong Kong, Paris has a low-rise skyline, with planners keen to preserve the look of its elegant 19th-century boulevards.

What skyscrapers there are have been pushed to the edge of the city centre, to leave a clear view to the iconic Eiffel Tower, and efforts have been made to attract global business to the outlying La Défense district.

But despite the triumph of its architecture, the First has so far not proved a hit with tenants. Only half of its office space, 80,000 square metres spread over 52 floors, has so far been allocated.

Building on the €300 million tower began in 2008. The first tenant, accountancy giant Ernst and Young, will move in during the second half of the year.