U.S. President Barack Obama and Turkish Prime Minister Recep Tayyip Erdogan expressed concern Friday that renewed violence in Israel and the Gaza Strip would damage the Middle East peace process.

"The two leaders shared their concerns about the dangers to civilian populations on both sides and expressed their common desire to see an end to the violence," the White House said, after Obama called the Turkish leader.

The U.S. power grid is susceptible to terrorists and could take weeks or even months to repair if attacked, a study warns.

The findings come shortly after megastorm Sandy hit New York City and the New Jersey coast late last month, causing widespread devastation and outages.

The United States on Thursday blamed Hamas for an explosion of violence in Gaza after salvoes of rockets were fired into Israel in retaliation for the killing of the group's military chief.

Expressing regret for the victims on both sides of the conflict, White House spokesman Jay Carney said there was "no justification" for the violence on the part of Hamas, saying it "does nothing to help the Palestinians."

Mitt Romney said President Barack Obama won by showering "gifts" on women, African American and Hispanic supporters, in his first published remarks since conceding last week's election.

The remarks came as Republicans have called for greater outreach to women and minorities after their unexpectedly lopsided defeat, and drew an angry response from Louisiana Governor Bobby Jindal, a rising star in the party.

The Chairman of the Joint Chiefs of Staff on Thursday said he was confident General John Allen would be promoted to NATO supreme commander in Europe despite his being linked to a sex scandal.

Allen, the top US commander in Afghanistan, is currently under investigation over thousands of emails exchanged with the woman who inadvertently led the FBI to CIA director David Petraeus's mistress, leading to his resignation.

President Barack Obama said Wednesday the United States is encouraged by Syria's new opposition coalition but is not ready to crown it the sole legitimate representative of the Syrian people.

"We're not yet prepared to recognize them as some sort of government in exile, but we do think that it is a broad-based representative group," Obama told reporters at the first news conference since his re-election.

President Barack Obama promised to launch a new diplomatic push to solve the longstanding crisis over Iran's disputed nuclear program, saying there was still a "window of time" to end the standoff.

His comments came amid speculation about possible direct U.S. talks that surfaced just before the U.S. elections and has gone up in volume since Obama's reelection.

The head of the U.S. Africa Command says Mali's military will take months to rebuild — even as West African nations and their Western backers examine ways of dislodging al-Qaida from the country's vast northeast.

Gen. Carter Ham says a weekend agreement by west African bloc Ecowas provided the "broad outlines" of a possible military intervention led by Mali's government against al-Qaida in the Islamic Maghreb and its allies.

Top U.S. General Carter Ham on Wednesday urged a global fight against the al-Qaida group based in Africa saying it could "export violence" to the West.

Ham, the head of the U.S. Africa Command, also said that the al-Qaida in Islamic Maghreb (AQIM) was linked to a deadly September 11 attack on the U.S. mission in Benghazi that killed U.S. ambassador to Libya Christopher Stevens and three others.

U.S. President Barack Obama should use his second term to concentrate on "the real problem in the region," the Israeli-Palestinian conflict, Syrian Deputy Foreign Minister Faisal Muqdad said on Wednesday.

"We hope during the second term of President Obama, he pays more attention to the real problem in the Middle East, which also affects the people of the United States, namely the Palestinian issue, which must be resolved on the basis of international legitimacy," he said in an interview with AFP.