A suicide bomber blew himself up at the entrance of a police academy in the Yemeni capital Sanaa on Wednesday, killing 20 people and wounding dozens more, a security official told Agence France Presse.

Iran is "100 times stronger" today than 30 years ago despite the multitude of Western sanctions imposed since the 1979 Islamic revolution, Iran's supreme leader Ayatollah Ali Khamenei said on Wednesday.

"Westerners are making much hype about sanctions against Iran but they don't understand that they have vaccinated the Iranian people themselves by imposing sanctions over the past 30 years," Khamenei said, quoted by state television.

A separatist from Yemen's southern movement was killed and four other people were wounded, including two women, in clashes with police in the port city of Aden on Wednesday, a local activist said.

"The police came into the Mansoura district and opened fire after residents came out to protest the police presence," Nizar al-Saeedi told Agence France Presse, adding that "one person was killed and four others were wounded."

Israeli President Shimon Peres has warned of the demographic consequences on the Jewish state of ongoing settlement in the occupied West Bank.

"Israeli settlements in densely populated Arab areas could bring about a demographic change about which we would do well to think hard about before acting," he said in remarks broadcast on both army radio and Israel public radio.

Syria's main exiled opposition group on Wednesday slammed Russia for giving a green light to violence after failing to convince Moscow to drop its support for President Bashar Assad.

Syrian National Council (SNC) chief Abdel Basset Sayda met Foreign Minister Sergei Lavrov in rare talks at the Russian foreign ministry but could not detect any shift in the Russian policy that has angered opponents of Assad.

Iran has warned the media against the publication of reports concerning the impact of Western sanctions, urging it to cooperate so that "the country is not hurt," local newspapers reported on Wednesday.

"Our country is not in a position to allow the media to publish (any) news or analysis which is not compatible with the regime's and national interests," said Mohammed Hosseini, the Minister of Culture and Islamic Guidance, whose ministry oversees the Iranian print media and official news websites.

Fifty-four migrants trying to reach Italy died of thirst when their inflatable boat ruptured in the Mediterranean, according to testimony from the sole survivor, the U.N. refugee agency said.

The rescued man, who drank sea water to survive, was spotted clinging to a jerry can and the remains of the stricken boat off the Tunisian coast on Monday night by fishermen who alerted the coast guard, the UNHCR said.

Egypt's Supreme Constitutional Court froze on Tuesday a presidential decree reinstating the Islamist-led parliament, hours after the lower house convened in defiance of the judiciary and military.

The top court's decision is expected to heighten a crisis that has raged since President Mohamed Morsi, a former member of the powerful Muslim Brotherhood, issued the decree Sunday just eight days after taking office.

Red Crescent staffer Khaled Khaffaji, shot during overnight in the Syrian province of Deir Ezzor, died on Tuesday, bringing to 56 the number of deaths across the strife-torn country, monitors said.

The Red Cross Red Crescent condemned Khaffaji's killing, saying "this is the second time in less than a month that a member of the Red Crescent has been killed while on duty."

The United States is aware of a Russian naval flotilla headed for a Syrian port but does not yet see cause for concern, the White House said Tuesday.

"We currently have no reason to believe this move is anything out of the ordinary but we refer you to the Russian government for more details," Erin Pelton, a spokeswoman for the National Security Council, told Agence France Presse.