caracas venezuela opposition say tuesday week plan political dialogue dominican republic president nicolas maduro government postpone regional guarantors go international negotiation process go ahead foreign minister invite opposition negotiator luis florido say refer potential presence latin american foreign minister talk negotiations ease bitter long-running political crisis opec nation schedule wednesday previous dialogue efforts end recriminations two side concrete progress opposition coalition previously accuse maduro government block presence foreign minister week talk tuesday say appear schedule problem immediate response officials opposition principal demand free fair condition 2018 presidential election also want freedom jail activists autonomy opposition-led congress foreign humanitarian aid corridor help alleviate venezuela unprecedented economic crisis maduro accuse opponents conspire unite state right-wing international campaign oust socialist government via coup government seek guarantee violence recognition pro-maduro constituent assembly override congress least 125 people die four months often violent protest maduro early year foes say dictator wreck once-prosperous economy maduro ally accuse opposition prefer violence dialogue debt refinance talk international investors begin successfully caracas monday government say though creditors say discussions fruitless venezuela opposition say talk government delay