German airline Lufthansa said Friday it has agreed in principle to sell its loss-making unit British Midland to the International Airlines Group, the holding company of British Airways.

"Deutsche Lufthansa AG and International Consolidated Airlines Group have reached an agreement in principle on the sale of British Midland to IAG," the German carrier said in a statement.

Cuba announced Thursday it will allow real estate to be bought and sold for the first time since the early days of the revolution, the most important reform yet in a series of free-market changes under President Raul Castro.

The law, which takes effect November 10, applies to citizens living in Cuba and permanent residents only, according to a red-letter headline on the front page of Thursday's Communist Party daily Granma and details published in the government's Official Gazette.

Occupy Wall Street protesters declared victory after thousands of demonstrators shut down one of the nation's busiest shipping ports late Wednesday, escalating a movement whose tactics had largely been limited to marches, rallies and tent encampments since it began in September.

As a voice over a bullhorn said "The night is not over, yet," protest organizers told demonstrators to head back to the downtown plaza where the Oakland movement has been based for more than a month. The Occupy encampment across the street from City Hall also was the scene of intense clashes with authorities last week.

World stocks fell Thursday for the fourth straight day as a European deal to bail Greece out of its financial mess appeared to be on the verge of unraveling.

Markets in Europe were down in early trading following another session of losses in Asia. Britain's FTSE 100 dropped 1.4 percent to 5,405.19 and France's CAC-40 lost 1.6 percent. Germany's DAX slid 2.2 percent to 5,833.69.

Oil prices fell to near $91 a barrel Thursday in Asia after Germany's leader said a Greek vote in December on a debt bailout package could lead to Greece leaving the euro zone.

Benchmark crude for December delivery was down $1.10 at $91.41 a barrel at late afternoon Singapore time in electronic trading on the New York Mercantile Exchange. The contract rose 32 cents to settle at $92.51 in New York on Wednesday.

The leaders of the world's most powerful economies confronted a new financial crisis Thursday as they began a G20 summit with markets in plummeting and Greece facing a forced exit from the euro.

As France and Germany tried to bully Athens back into line, the Eurozone debt crisis threatened to engulf Italy, which saw the costs of its borrowing hit record highs amid fears over Europe's bail-out mechanism.

Dubai's Emirates airline posted Thursday a 76 percent drop in net profits in the first half of its financial year, reaching 827 million dirhams ($225 million) as fuel cost surged, a statement said.

The state-owned carrier, which posted net profits of 3.4 billion dirhams ($925 million) in the corresponding period last year, said climbing fuel prices have inflicted an extra cost of one billion dollars.

The U.N. development agency called Wednesday for a currency transaction tax to help the world's poorest countries deal with the effects of climate change.

"In updated analysis prepared for this report, the North-South Institute estimates that a tax of 0.005 percent would yield around $40 billion a year," said the UNDP's annual Human Development Report.

Britain's state-rescued Lloyds Banking Group said on Wednesday its chief executive Antonio Horta-Osorio had temporarily stepped down due to illness and was being replaced by its chief financial officer.

Horta-Osorio, 47, who became chief executive in March, is understood to be suffering from fatigue, according to sources.

Even as Europe's debt crisis spirals out of control, Wall Street is casting an eye on a fast-approaching congressional deadline that could spark a debt crisis this side of the Atlantic.

U.S. investors -- for weeks preoccupied with the tumult raging in Greece and the broader Eurozone -- are starting to look with trepidation at the November 23 deadline for a Congressional committee to agree to $1.2 trillion in deficit cuts.