A “disappointing” fortnight of UN talks in Bonn, Germany, has left much work to be done just five months before a crucial climate summit, diplomats and analysts said after negotiations failed to make progress on efforts to tackle climate change.

At the closing session on Thursday, developing nations expressed disappointment at the scant progress at the midyear session on major issues, in particular on setting up a finance facility to deal with mounting losses from extreme weather and rising seas...