1. Putin says world should not underestimate threat of nuclear war
In his year-end press conference on Thursday, Russian President Vladimir Putin warned the world against underestimating the threat of nuclear war, adding that he believed the "the world arms control system has collapsed".
Putin also remarked on several other international issues, including Ukraine and sanctions placed on Russia by the West.
On Ukraine, the Russian president said the recent spat between Russian and Ukrainian ships in the Black Sea was orchestrated by President Petro Poroshenko to boost ratings "at the expense of [Ukraine's] citizens".
Referring to the Skripals poisoning case in the UK, Putin called resulting sanctions "an attack on Russia to curb its development".
2. Repeated drone sightings halt flights at London's Gatwick Airport
London's Gatwick Airport has been forced to suspend flights after two drones were repeatedly sighted near its runways.
Take-offs and landings have been disrupted since Wednesday night.
In a statement posted to Twitter early on Thursday morning, the airport said its runways were initially closed for six hours between 21h and 3h (Thursday) GMT. However, the airfield only reopened for a mere 44 minutes before being closed again after a further sighting of the drones.
"Unfortunately, this has led to a number of flights being diverted to other airports while aircraft have also been unable to depart from Gatwick," the airport said in the statement.
Sussex Police has opened an investigation to find the drone operator.
3. France and the UK lead criticisms of Trump's decision to pull US troops from Syria
The decision of US President Donald Trump to pull US troops from Syria has been met with widespread criticism from a number of experts and allies who maintain the battle is not over.
Leading the criticism from Europe was French Defence Minister Florence Parly, who said that while so-called Islamic State may have been weakened the fight was far from over.
"Daesh is not yet wiped from the map," she said in a tweet. "It is necessary to definitively defeat militarily the last pockets of this terrorist organisation."
A UK government spokesperson said "much remains to be done and we must not lose sight of the threat [Daesh] pose. Even without territory, Daesh will remain a threat".
4. Pussy Riot on Russian music censorship: 'The only thing that should be banned is the FSB' (Euronews interview)
Euronews met with Pussy Riot members Olga Kuracheva and Veronika Nikulshina in Lyon, France, to talk about life after they protested on the World Cup field, the pressure on Russian rappers and modern youth.
5. Man arrested in connection with the killing of two Scandinavian tourists is part of an armed group, prosecutor says
A suspect arrested in connection with the killing of two Scandinavian tourists in Morocco's Atlas Mountains is part of an armed group, the Moroccan public prosecutor said on Wednesday.
The armed group was not named in the prosecutor's statement.
The two women, from Norway and Denmark, were found dead near the village of Imlil in Morocco's Atlas Mountains on Monday.
6. French minister says "door remains open" should Britain hold second Brexit referendum
The European "door remains open" to the UK should a second Brexit referendum go ahead, the French Minister for European Affairs, Nathalie Loiseau, said in a tweet on Thursday.
Maintaining the stance taken by other European leaders, Loiseau said British Prime Minister Theresa May's current deal was the "only and the best possible agreement" and warned that a delay from parliament in ratifying the deal would force Europe to "accelerate preparation for the lack of agreement".
Theresa May as repeatedly ruled out the possibility of a second referendum.
As it happened on Thursday, December 20
This is how we covered key developments this morning: