The P5+1 nuclear negotiations with Iran continue apace this weekend, with officials describing Saturday’s talks in Vienna as a “breakthrough,” and one which now has the two sides sitting on an unofficial draft agreement which could end up serving as the basis for a final pact.

Iranian Foreign Minister Javad Zarif conceding that despite the progress, the final deal still isn’t necessarily clear, and that some difference remain and will require significant effort to move past. Exactly what remains to resolve is unclear.

The IAEA has also appeared more optimistic about the final deal in recent comments, saying they believe that questions about Iran’s past nuclear work, an issue which they’ve sat of for many years, can be resolved fairly simply by year’s end.

Even if there are still i’s to dot and t’s to cross, the breakthrough suggests that the deal is closer than ever, and many officials are openly talking about the final pact being reached within the week, putting an end to the disputes over Iran’s civilian nuclear program once and for all.