By Henri Astier BBC News, Paris

Mr Sarkozy's first priority will be to form a new cabinet

Following his comfortable victory at the polls, Nicolas Sarkozy took a few days' holiday to recover from an intense, two-round campaign.

But what will the new French president do now he has been inaugurated as President?

His first priority will be to form a new cabinet - which is expected to include not just members of his centre-right UMP party, but also centrists and left-wing defectors.

He will then have two main tasks - preparing for parliamentary elections on 10 and 17 June, and kick-starting what he calls his plan for "rupture".

"We must act - that's what the French expect," Mr Sarkozy's campaign director, Claude Gueant, told France's RTL radio.

"The operational team must be ready very soon," he added.

'Absolute power'

How soon, however, is still unclear.

The UMP already has an overwhelming majority in the outgoing assembly, and nothing can stop the president pushing through some of his programme before the June polls.

No one is there to stop you making mistakes - when absolute power is mistaken, it is absolutely mistaken Centrist leader Francois Bayrou

On the other hand, Mr Sarkozy may decide to wait until a new assembly is in place.

Traditionally French voters have given newly elected presidents a strong parliamentary majority, boosting their legitimacy further.

Either way, the opposition is worried about being crushed into irrelevance.

"The victors want to decide everything," Socialist party chairman Francois Hollande said. "We need countervailing powers."

But the strongest warning came from centrist leader Francois Bayrou.

"Absolute power can be a comfort," he said. "You can decide what you like, and no one is there to oppose you."

But at the same time, Mr Bayrou added: "No one is there to stop you making mistakes - when absolute power is mistaken, it is absolutely mistaken."

Battles

Mr Sarkozy's plans are sweeping indeed.

He wants to drive growth by rewarding effort and spurring competition - the kind of market reform undertaken in most EU countries in the 1990s, but which have repeatedly failed in France.

SARKOZY: KEY POLICIES Exempt overtime (above 35 hours) from taxes and social security charges Minimum sentences for repeat offenders, tougher sentences for juveniles Selective immigration that favours arrival of qualified workers Increase taxes on polluters Oppose Turkish EU membership

His economic programme includes incentives to encourage overtime - summed up by his slogan "work more to earn more" - as well as deep tax cuts.

The president-elect wants to reform the benefits system by forcing the unemployed to accept work, and by scrapping the pensions privileges enjoyed in the public sector.

He has also pledged to take on restive state workers by instituting a "minimum service" for transport during strikes, and by not replacing half the workers retiring from public service.

Mr Sarkozy is tough on crime and illegal immigration, and has promised to create a controversial new "ministry for immigration and national identity".

His clear victory has given the lie to those - both on the traditional right and left - who had argued that the French are not ready for root-and-branch reform.

Nevertheless, the contentious nature of his programme suggests bitter battles ahead.

The new president's opponents are mobilising for the legislative polls.

Opposition moves

For the Socialists, the challenge is to avoid recriminations following their third consecutive defeat in a French presidential election.

The Socialists are licking their wounds after the election defeat

Dominique Strauss-Kahn - a former finance minister who wants to take the Socialist Party closer to centre - has already begun challenging both Mr Hollande and presidential candidate Segolene Royal (who happen to live together as partners).

A change of leadership among the Socialists, however, is unlikely until after the legislative elections - when the real battle for the soul of the party begins in earnest.

The most noticeable realignment will take place in the centre of French politics.

Mr Bayrou is hoping to capitalise on his relative success in the first presidential round to create a new party in the centre.

His Democratic Movement will be launched later this week, and is expected to field candidates in all constituencies.

Unlike the old UDF it is replacing, the new group will not be allied to the right - reflecting an influx of new sympathisers from the centre-left.