Today's World News covering, Africa, Europe, Middle East

Turkey's main opposition party has said it will challenge the country's referendum result after the president won a vote to expand his powers.

North Korea has warned the US not to take provocative action in the region, saying it is "ready to hit back with nuclear attacks".

NASA has new evidence that the most likely places to find life beyond Earth are Jupiter's moon Europa or Saturn's moon Enceladus. In terms of potential habitability, Enceladus particularly has almost all of the key ingredients for life as we know it, researchers said.

In just the last week, the rookie commander-in-chief has presided over the use of some of the most powerful weaponry in the US arsenal, sending a signal that he is one President who relishes ordering the use of deadly force.

The Syrian government and rebel groups have begun an operation to move people away from four besieged towns, activists say.

A US military strike with a weapon known as the "mother of all bombs" (MOAB) killed 36 IS militants and destroyed their base, the Afghan defence ministry says.

The Trump administration plans to sell fighter planes to Nigeria despite concerns over rights abuses and a botched air strike that killed scores of civilians in January, US media say.

President Donald Trump’s deputy national security adviser, K.T. McFarland, has been asked to step down after just three months, US media say.

Egypt's President Abdul Fattah al-Sisi has announced a three-month state of emergency after attacks on two Coptic churches that left at least 44 dead.

The Trump administration warned that it’s ready to take further military action if the regime of Bashar al-Assad wages another chemical attack, even as this week’s missile strike ratcheted up tensions with Russia.

Syrian leader Bashar al-Assad should have no role in a future Syria, US Secretary of State Rex Tillerson says.