Paris - France's president-elect Francois Hollande faced an immediate economic challenge on Monday as turmoil in Greece and doubts about his own plans threatened to plunge the eurozone back into a debt crisis.
Stocks tumbled across Asia and on opening in Europe, the euro took a new battering and the spread in yields between French and German bonds widened, as markets eyed political developments in the eurozone with concern.
The Socialist won power on Sunday in a close race against France's outgoing right-wing leader Nicolas Sarkozy, triggering joyful street parties, but now faces a crowded calendar of international financial summits.
A date for the formal handover of power has not yet been set - it should come before May 15 - but Hollande began consultations with European allies, including telephone talks with Germany's Chancellor Angela Merkel.
Asian markets and the euro slumped on Monday amid concerns that victories for Hollande in France and for opposition parties in Greece marked a backlash against austerity measures designed to slash eurozone public deficits.
The single currency dropped to $1.2998, down from $1.3082 on Friday in New York, while in Tokyo stocks closed 2.78% lower, Sydney finished 2.15% lower while Hong Kong ended 2.61% off.
In Europe, the Paris CAC 40 opened 1.57% lower, shares in Athens plunged 7.6% while Frankfurt's DAX was down 2.2%.
Interest rates on France's benchmark 10-year bonds rose in early trading, while Germany's hit historic lows, the wider spread suggesting that investors are seeking a safe haven in the eurozone's star economic performer.
Hollande, while no radical, has vowed to slow the pace of Sarkozy's public spending cuts and renegotiate the EU fiscal pact, under which the 17 members of the single currency bloc agreed tough measures to slash their deficits.
Debt-wracked Greece is facing turmoil after parties opposed to its EU and IMF-led austerity programme stripped the coalition government of its majority and an extreme right-wing group won its first seats in 40 years.
In France, Hollande's economic plan replaces some of Sarkozy's cost-cutting with higher taxes on the wealthy but still foresees a balanced budget by 2017, despite a hiring spree in education and a return to retirement at 60.
Bond markets have had six months to get used to the idea of a return to Socialist rule and panic is not expected, but if concerns over Paris lead to higher borrowing costs then the deficit target will be harder to meet.
In his victory speech on Sunday, Hollande admitted that the eyes of Europe and the world were on France, but promised to carry through on his promise to revise the hard-won EU stability pact to focus more on growth than cuts.
"You are much more than a people who want change. You are already a movement that is rising across all of Europe and maybe the world," he told the cheering masses celebrating his victory in Paris' iconic Bastille Square.
"This is the mission that is now mine: to give the European project a dimension of growth, employment, prosperity - in short, a future," he had said earlier, at another speech in his electoral stronghold of Tulle.
"This is what I will say as soon as possible to our European partners and first of all to Germany," he said. "We are not just any country on the planet, just any nation in the world, we are France."
Germany's Merkel had made no secret during the campaign of her support for fellow right-wing and EU fiscal pact architect Sarkozy, but she wasted no time in reaching out to Hollande once his victory was confirmed.
Merkel invited Hollande to Berlin for talks and her Foreign Minister Guido Westerwelle told reporters: "We will work together on a growth pact. I am confident the Franco-German friendship will be further deepened."
After seeing Merkel shortly after his inauguration Hollande will face a series of international meetings, including a G8 summit in the United States on May 18 and 19 and a NATO gathering in Chicago on May 20 and 21.
Hollande's communications director Manuel Valls confirmed Monday that France would use the summit to "announce the withdrawal of its forces from Afghanistan between now and the end of the year".
US President Barack Obama invited Hollande for talks at the White House, amid concerns about this pledge to hasten the return of France's 3 300-strong contingent out of the Nato-led force in Afghanistan.
Defence officials in Kabul doubted this was even feasible, but Afghan commanders insisted they were ready to take responsibility for their own fate.
China's China's President Hu Jintao had sent a message of congratulation to Hollande, promising to work with him. Spain's conservative Prime Minister Mariano Rajoy said he felt "obliged" to work with his northern neighbour.
Hollande will have to complete the task of casting his new government in the coming days, before his party sets off on the campaign trail for France's June parliamentary election, when he will hope to secure a ruling majority.
Sarkozy congratulated Hollande on the win and signalled that he intends to step back from frontline politics.