Following the resumption of negotiations to revive the 2015 Iran nuclear deal, negotiators from both sides have expressed hope the talks will bear fruit.
The EU official chairing the talks was upbeat following the first sit-down in Vienna on Monday, saying he expects important things to be agreed upon over the coming weeks.
Iran's deputy foreign minister, leading Tehran's team of negotiators, also said he was optimistic.
In addition, Russia's envoy tweeted that the talks had started quite successfully.
However, analysts warn such early optimism is not justified, saying the problems may arise when they get into the weeds and past the pleasantries.