At least 36 people were killed during the weekend's clashes between Libyan Special Forces and Islamist militants in Benghazi, security officials said.
The government said more than 150 people have died, many of them civilian, in the capital Tripoli and Benghazi in two weeks of fighting as clashes forced UK and other foreign diplomats to pull out of the country.
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PM spokesman's comments come following reports that the EU is secretly drawing up plans for greater military cooperation across the EU.
The Labour politicians put their alleged differences aside to jointly highlight how remaining in the EU could help fight climate change.
Late sunshine here and there this evening - but more cloud for southern Scotland, northern England and Northern Ireland again.