In this Tuesday, May 7, 2013 file photo, Iranian Foreign Minister Ali Akbar Salehi, left, speaks at a joint news conference as his Jordanian counterpart, Naser Judeh, listens in Amman, Jordan. Salehi wrote in an opinion piece in the Lebanese daily Al-Akhbar Wednesday, May 8, that it is up to the Syrian people to choose their political system and president, suggesting Tehran is not wedded to Assad's continued rule. (AP Photo/Raad Adayleh, File)

A problem with a fiber optics cable was responsible for an Internet outage that cut off civil war-ravaged Syria from the rest of the world for nearly 20 hours, state media said Wednesday.

Internet service stopped abruptly Tuesday evening, prompting speculation that the regime had pulled the plug, possibly as a cover for military action. However, no large-scale military offensives were reported Wednesday and the opposition did not accuse the regime of sabotage.

In the past, the regime halted Internet service in selected areas during government offensives to disrupt communication among rebel fighters. The last nationwide outage, for two days in November, coincided with a major military operation near the capital, Damascus, and its international airport.

A U.S.-based Web watcher said the problem would have to occur somewhere inside Syria for the entire country to be affected, although it was impossible to tell from a distance exactly what happened.

Jim Cowie of Renesys, a company that monitors online traffic, said Syria is serviced by three underwater cables, but a problem in one of those would not be sufficient to cut off Internet nationwide.

Preventing Internet access has become a tool of last resort for governments trying to suppress unrest, particularly during the Arab Spring protests that eventually toppled leaders in four countries.

Tunisia, the birthplace of the Arab Spring, experienced frequent Internet disruptions during its period of mass protests, while service in Egypt was shut down for almost a week ahead of the ouster of President Hosni Mubarak in February 2011.

The Internet has also been an important tool in the bloody battle to topple Assad, now in its third year. With the Syrian government restricting foreign media access to the country, anti-regime activists talking on Skype and amateur videos posted online became important sources of information.

In rebel-controlled areas in the north and east of Syria, the regime cut off Internet service early in the uprising, forcing activists to use more expensive satellite phones.

Ahmad al-Khatib, an activist in the Jabal al-Zawiya region in the northwestern province of Idlib, said Internet has been down in his area for more than a year.

"It was normal news for us yesterday. It did not affect us," he said via Skype. "Those who were affected are activists who use 3G and they are mostly activist in regime-controlled areas."

He said that although 3G can be monitored by authorities, activists in Damascus still rely on it since those owning a satellite phone risk being flagged as potential rebel sympathizers.

Also Wednesday, the leader of the radical rebel group Jabhat al-Nusra was wounded by regime shelling in southern Damascus, according to the Britain-based Syrian Observatory for Human Rights. Several other fighters were injured in the incident, the Observatory said. The leader was identified by his nom de guerre, Abu Mohammed al-Golani.

Al-Nusra, which has pledged allegiance to the al-Qaida terror network, is one of the dominant forces in the civil war, and its fighters are often found on the front lines.

On the diplomatic front, the international envoy to Syria, Lakhdar Brahimi, welcomed a new U.S-Russian initiative to end the 26-month-old Syria conflict through negotiations.

A decision to convene an international conference later this month to build on a transition plan for Syria is "the first hopeful news" concerning Syria "in a very long time," Brahimi said Wednesday.

The goal of the plan, set out in Geneva last year, is to bring the Assad regime and opposition representatives together for talks on an interim government. Each side would be allowed to veto candidates it finds unacceptable.

The proposal also calls for an open-ended cease-fire and the formation of a transitional government to run the country until new elections can be held.

Brahimi has repeatedly expressed frustration over the failure to find a political solution in Syria, and has lamented the divisions on the U.N. Security Council that have prevented any international action.

The main opposition group, the Syrian National Coalition, said Wednesday it welcomes efforts to reach a political solution, but said any transition must begin with the departure of Assad and officials in his regime. Syrian officials have said that Assad will stay in his post until his seven-year term ends next year and he will run again.

Meanwhile, U.S. officials said the Obama administration is providing $100 million in new Syria aid, but the money is for humanitarian purposes only and not linked to any decision on arming Syrian rebels.

The announcement will be made by Secretary of State John Kerry on Thursday in Rome, where his diplomacy includes a meeting with Jordan's foreign minister, the officials said.

The new funds will help support 1.4 million Syrian refugees, including many in U.S. ally Jordan, and hundreds of thousands of other civilians still trapped by the violence inside Syria's border. Total U.S. humanitarian assistance in the two-year war will climb to $510 million.

The U.S. officials weren't authorized to speak publicly on the matter ahead of Kerry's announcement and demanded anonymity.

The Obama administration has said it is considering providing weapons to vetted units in the armed opposition, among other military options, following last week's revelation that U.S. intelligence suggests the Assad regime has used chemical weapons. The U.S. also is looking for ways to halt the violence that has killed more than 70,000 people.

But the U.S. maintains deep reservations about providing direct military assistance, given the growing presence of al-Qaida-linked and other extremists in the rebel ranks.