U.S. President Barack Obama said Tuesday that Syrian leader Bashar Assad has missed a series of chances for reform, as he also denounced an attack on the U.S. embassy in Damascus.

Assad, Obama told CBS television, has "missed opportunity after opportunity to present a genuine reform agenda.

A volley of U.S. missile strikes killed 25 militants after destroying their compounds in Pakistan's lawless tribal areas on the Afghan border, security officials said Tuesday.

Twin drone attacks hit militant strongholds in North and South Waziristan 12 hours apart, as the United States announced it was suspending more than a third of its annual military aid to Pakistan, bringing relations to a new low.

President Nicolas Sarkozy said Tuesday that France would withdraw a quarter of its 4,000 troops from Afghanistan by the end of next year, becoming the latest NATO power to downsize its combat mission in the war-torn country.

The French leader announced the withdrawal after jetting in on a surprise visit to meet troops stationed in Sarobi district, northeast of Kabul, and to be briefed on progress against the Taliban by a French general.

The Pakistani military said Monday it was capable of fighting without American assistance, adding that it had not been informed officially of a U.S. decision to suspend $800 million worth of aid.

"The army in the past as well as at present has conducted successful military operations using its own resources without any external support whatsoever," military spokesman Major General Athar Abbas wrote to Agence France Presse.

A top aide to U.S. President Barack Obama called Sunday on Yemen's injured President Ali Abdullah Saleh to sign a deal transferring power, during a face-to-face meeting in Saudi Arabia.

Saleh, who has ruled Yemen since 1978, received top U.S. counter-terrorism official John Brennan in a hospital in Riyadh where he is recovering after being badly burned in a bomb attack at his presidential palace last month.

Two Air Force fighter jets intercepted a civilian aircraft over Camp David, Maryland on Saturday, according to a statement released by North American Aerospace Defense Command (NORAD).

"The civilian aircraft, which was out of radio communication, was intercepted and departed the Temporary Flight Restricted area, it landed without incident," NORAD officials said in a press release.

World leaders on Saturday hailed the birth of the world's newest nation, the Republic of South Sudan, as a historic event bringing to a close 50 years of conflict in northeastern Africa.

U.S. President Barack Obama led official recognition of the country, calling it "another step forward in Africa's long journey toward opportunity, democracy and justice."

Sudan's Omar al-Bashir said on Saturday that the newly independent Republic of South Sudan's success "will be our success," and renewed his call for an end to U.S. sanctions against his country.

"We fulfill our commitment to help the new state of South Sudan in its first steps, because we want it to succeed, and because its success will be our success," Bashir said in a conciliatory speech to tens of thousands of southerners at the official independence ceremony in Juba.

The "strategic defeat" of al-Qaida is "within reach", U.S. Defense Secretary Leon Panetta said Saturday as he arrived on a surprise visit to Afghanistan as the U.S. prepares a gradual drawdown of troops.

Panetta, who took office on July 1 to replace the outgoing Robert Gates, arrived in Kabul for a trip to include talks with President Hamid Karzai over the transition of some NATO-held areas to Afghan control starting mid-July.

U.S. President Barack Obama urged Democrats and Republicans Saturday to take a "balanced approach" to cutting deficit before a new round of key talks aimed at averting a debt default.

Obama said the two parties must address challenges like the solvency of Medicare, a government-run health insurance program for seniors and also insisted on closing tax loopholes and deductions for the wealthiest Americans.