“He was a global thinker, who saw things ahead of others. He was an advocate of economic progress, but also made tireless efforts to advance peace and stability in our region.”

Talks with Iran on its nuclear programme are intensifying as the deadline for a deal at the end of the month draws close.

The talks, attended by Iran and the P5+1 group, the US, China, Russia, France, the UK and Germany, are intended to seek a deal to prevent Iran from seeking a nuclear agreement.

The US Secretary of State John Kerry and his German and French counterparts have cancelled their travel plans for the last few days of the talks, in order to push for a resolution ahead of the March 31 deadline.

Iran, which denies it is pursuing nuclear weapons, is hoping to achieve the lifting of international sanctions through a deal.

US officials said all parties, including Iran, had agreed "there needs to be a phased step by step reciprocal approach", so that Iran's steps to scale back its nuclear programme are met with a phased lifting of sanctions, the BBC said.

The Nigerian elections continued for a second day, after technical problems hit around 300 polling stations.

About 300 out of around 150,000 were affected by the glitch, which left voters, including President Goodluck Jonathan, unable to cast their vote.

"There should have been a test-run for a smaller election before deploying it for an election of this magnitude," said Mr Jonathan's presidential campaign spokesman Femi Fani-Kayode.

Polling stations were also hit by attacks from unknown gunmen.

A Somalian diplomat was among at least 20 people who died when Al Shabaab militants launched an attack on a hotel in Mogadishu.

The Maka al-Mukarama Hotel was targeted by a car bomb on Friday evening, before being stormed by armed suicide bombers, who all died in the attack.

Security forces retook the hotel on Saturday morning. Somalia's ambassador to the United Nations in Geneva Yusuf Mohamed Bari Bari died in hospital, after being admitted with serious injuries.

Information Minister Mohamed Abdi Mareye led a government delegation to the scene on Saturday morning.

Syrian rebels captured the key Syrian city of Idlib from government forces, according to the Syrian Observatory for Human Rights.

The monitoring group said that the Ahrar al-Sham, Jund al-Aqsa and Nusra Front groups had taken the city on Saturday.

The Syrian government has not confirmed the loss, with state television saying, "The army is fighting fierce battles to restore the situation back to what it was."