France expressed concern Friday after the U.N. nuclear watchdog said Iran had installed advanced centrifuges in a key nuclear plant, calling it a "step backwards."

The U.N. International Atomic Energy Agency said that Tehran "had started the installation of IR-2m centrifuges" at a plant in Natanz in the center of the country.

Japanese Premier Shinzo Abe headed to the White House Friday on a mission to send a strong signal to China, which has stepped up pressure on the conservative leader over a tense territorial row.

Two months after his right-leaning Liberal Democratic Party swept back into power, Abe opened his first meeting with President Barack Obama in hopes of showing the region that there is no daylight between the two allies.

Public workers, small political parties and non-profit organizations will stage protests Saturday against government austerity measures in dozens of Spanish cities, with the biggest demonstration expected to be held in Madrid.

Nurses, doctors, students, miners and members of Spain's "indignant" movement against economic inequality are set to join in the so-called "citizens' tide" against the steep spending cuts and tax hikes imposed by Prime Minister Mariano Rajoy's conservative government to slash the public deficit.

Attackers in Nigeria including some dressed as soldiers have killed 10 members of the same family with half of the victims under the age of six, an official in central Plateau state said Friday.

"The attack was in the night around 8:00 pm (1900 GMT Thursday) where a family of 10 were completely murdered," the governor's spokesman Pam Ayuba told Agence France Presse, adding that some of the attackers wore military uniforms.

A 6.1 magnitude earthquake hit southwest Argentina Friday but caused no damage or injuries, the U.S. Geological Survey and local authorities reported.

The earthquake was "within the limit of moderate to severe, but it was 672 kilometers (417 miles) underground and was not perceived by the population," Argentina's National Institute of Seismic Prevention said.

Footage of a young man in psychological distress who asked for police protection but later died after being brutally battered by a crack six-man police unit caused shockwaves across Belgium on Friday.

The disturbing scenes of police brutality that took place in early 2010 in the suburbs of the port city of Antwerp were aired on the VRT Dutch-speaking television network in a documentary late Thursday.

NATO may station up to 12,000 troops in Afghanistan to train and assist Kabul's forces after the alliance's combat mission there against the Taliban ends in 2014, U.S. officials said Friday.

U.S. Pentagon spokesman George Little said NATO was considering deployment of between 8,000 and 12,000 troops, including any U.S. contribution, but no final decision has yet been made.

U.S. President Barack Obama sent 40 additional soldiers to Niger to help with intelligence efforts as French and African troops battle an Islamist insurgency in neighboring Mali, the White House said in a letter to Congress Friday.

The U.S. troops join another 60 or so already in the West African country, and are tasked with providing "support for intelligence collection and will also facilitate intelligence sharing with French forces conducting operations in Mali, and with other partners in the region," the president said.

Germany is not seeking to impose its will on the rest of Europe, the country's president said Friday, also urging Britain to stay inside the Europe it helped "save" after World War II.

President Joachim Gauck delivered an impassioned speech on Europe, his first since taking over the largely ceremonial office 11 months ago, lamenting that its economic crisis had also hit confidence in its "political project".

Turkey voiced hope that a presidential runoff in Cyprus Sunday would yield a "serious counterpart" for Ankara and pave the way for a peace deal between the island's Greek government in the south and its northern occupiers.

"I believe Christofias was a big joke," European Union Affairs Minister Egemen Bagis said in an interview to Agence France Presse this week, referring to President Demetris Christofias whose term runs out at the end of this month.