Leftist Venezuelan President Hugo Chavez admitted a relapse of his cancer late Saturday and designated Vice President Nicolas Maduro as his heir apparent in case "something happened" to him.

Speaking on national television, an emotional Chavez said a return of cancer cells was detected during his most recent visit to Cuba for medical examination, and he will return to the communist-ruled island as early as Sunday for another round of surgery.

Vietnam broke up an anti-China rallies in its two main cities and arrested around 20 people Sunday, activists told AFP, in the latest protests against Beijing as tensions flare over the South China Sea.

Around 200 protesters, some waving banners and chanting "Down with China's aggression!", were intercepted by security forces as they tried to approach the Chinese embassy in the capital.

Pakistan's President Asif Ali Zardari on Saturday visited a Pakistani schoolgirl who is recovering in a British hospital after she was shot by the Taliban for campaigning for girls' education.

Zardari also met with 15-year-old Malala Yousafzai's family during a private meeting at the specialist Queen Elizabeth Hospital in Birmingham, central England, where Malala was flown from Pakistan in October following the brutal attack on her school bus.

Sudanese authorities on Saturday shut a university after four students, originally from the conflict-plagued Darfur region, were found dead following an alleged crackdown on a tuition protest.

The order coincided with the arrest of students who tried to demonstrate in Khartoum after holding a news conference about the deaths, which they blame on authorities and their "militia."

Weapons including a rocket launcher were seized and an Egyptian man was arrested in the southern Italian port of Naples on Saturday, the ANSA news agency reported, citing police.

The weapons were discovered in a container, the agency said.

The traces of poison found in an autopsy on the exhumed remains of Turkish president Turgut Ozal, who died in office in 1993, were too minute to be lethal, the pro-government daily Sabah reported Saturday.

The insecticide DDT, heavy metal cadmium and radioactive substances polonium and americium were present in "minute doses", Sabah said, quoting a Forensic Medicine Council report to be released in the coming days.

North Korea said Sunday it was considering postponing a planned long-range rocket launch originally set for between December 10 and 22, citing unspecified problems during preparations.

The Korean Committee for Space Technology said its scientists and engineers were "considering seriously the possibility of readjusting the launch period".

A delegation of Congolese rebels has arrived in Kampala for talks with the government aimed at ending a crisis that has led to widespread rights abuses and displacement and sparked fears of an all-out regional conflict.

The negotiating team from the M23 rebel group arrived in the Ugandan capital late Friday, their spokesman Amani Kabasha told Agence France Presse Saturday.

Nelson Mandela was on Saturday admitted to a hospital for tests consistent with old age and is doing well, the office of South Africa's president, Jacob Zuma, announced.

"Former President Nelson Mandela has today, 8 December 2012, been admitted in hospital in Pretoria to undergo tests," Zuma's office announced. Mandela "is doing well and there is no cause for alarm," it added.

Silvio Berlusconi on Saturday ended weeks of speculation by announcing he would run again for the job of prime minister, the post he was forced out of last year.

"I am running to win," the leader of the right-wing populist People of Freedom (PDL) party told journalists in Milanello, near the northern city of Milan.