Iran, Russia and the United States have reacted positively to the opening exchanges in a first day of talks in Vienna aimed at rescuing an international agreement on Tehran's nuclear program.

Iran on Tuesday welcomed "promising" recent comments by US officials explicitly suggesting that the United States lift sanctions in order to return to the 2015 nuclear deal.

The death toll from a ferry accident in Bangladesh at the weekend rose to at least 34 after six more bodies were retrieved, officials said Tuesday.

The United States will on Tuesday join talks in Austria's capital Vienna aimed at salvaging an international agreement on Iran's nuclear programme, which Washington withdrew from in 2018.

The European Union's top two officials will pay a rare visit on Tuesday to Turkish President Recep Tayyip Erdogan aimed at testing his avowed commitment to improve uneasy ties.

At least 40 people have been killed and 58 injured in three days of clashes in Sudan's West Darfur state, the United Nations said Monday.

More than 1,800 inmates have escaped after heavily armed men attacked a prison in southern Nigeria using explosives, prison authorities said Monday, in one of the country's largest jailbreaks.

Russian President Vladimir Putin on Monday gave final approval to legislation allowing him to hold office for two additional six-year terms, giving himself the possibility to stay in power until 2036.

Moscow said Monday it was probing the death of a five-year-old child allegedly killed by Kiev forces in eastern Ukraine held by Russian-backed separatists.

Over the past week, fears have mounted of an escalation of a simmering conflict in eastern Ukraine, where government forces have battled separatists since 2014. 

Tribal clashes in Sudan's restive Darfur region have killed at least 18 people and wounded 54, a local doctors' committee said Monday.