berlin germany three would-be coalition partner go deep overtime talk saturday seek enough common grind climate migration policy form government stave prospect repeat election incumbent chancellor angela merkel realistic hope secure fourth term suffer losses september election awkward three-way conservative-liberal-green alliance four weeks talk party remain far apart adjourn night big stick point climate change green want emissions cut party see economically ruinous immigration merkel arch-conservative ally bavaria insist strict rule pro-business tax-cutting free democrat fdp liberals freshly return parliament four years wilderness green office 12 years neither keen give grind self-imposed deadline thursday wrap exploratory talk start formal coalition negotiations pass without agreement force conservatives promise concessions emissions cut green fdp leader christian lindner say talk wrap 1700 gmt sunday president frank-walter steinmeier former foreign minister play apolitical role say brinkmanship expect formal talk start always attempt party drive price tell weekly welt sonntag see past weeks different previous coalition negotiations green chairwoman simone peter say much early agree emissions policy undo without give detail bavaria christian social union csu face regional state elections next year fear far-right alternative germany afd could unseat 60 years fail secure tough immigration rule anathema left-leaning green among demand cap 200,000 per year number refugees germany take end practice allow successful asylum seekers bring immediate families join party anxious avoid repeat election fear could boost afd surge parliament first time september national election heterogeneous three-way coalition make necessary conservatives centre-left suffer punish election losses untested national level german party regroup last-ditch coalition push