Talks over Iran's nuclear programme are moving forward in Vienna, but Russia's ambassador said that work needs to be done before an agreement is reached.
Mikhail Ulyanov wrote on Twitter that negotiators still had a "whole spectrum of contentious issues that need to be settled".
Iran, the US and EU have been holding talks in Austria’s capital - along with China, Russia and the UK - in the hope of reaching a new deal to lift US sanctions and curb Tehran's nuclear programme.
The Russian envoy said he held a meeting with the EU's Enrique Mora, which focused on ways to move the talks forward and pave the way for an eventual agreement. Mr Ulyanov also met US special envoy on Iran Rob Malley and described the meeting as "pragmatic".
Negotiators have indicated that talks are likely to come to a close by the end of January or early February. All sides in Vienna have over the course of the talks said that time is limited and diplomatic overtures will not be endless.
Iran's lead negotiator Ali Bagheri also met Mr Mora on Monday evening as part of a series of bilateral meetings with the other parties including China and Germany, the UK and France.
US officials in Vienna does not directly negotiate with Iran, but rather the two sides speak through the EU and Russia.
The US has in the past expressed cautious optimism over the progress of the talks but has continued to warn Iran over its demands and conduct outside of the process.
Meanwhile, appetite to reach a deal among the American people is holding strong. A Morning Consult poll released Monday shows the majority of Americans, 56 per cent support talks with Iran and the lifting of sanctions if it would lead to more diplomatic talks.
According to the poll, the majority of Americans also disagree with the decision for the US to exit the deal. Former president Donald Trump withdrew from the nuclear accord in 2018 and imposed sanctions on Iran's economy.
His successor, President Joe Biden, has made the Iran nuclear deal a focus of his foreign policy but is facing a tough sell with Congress as midterms in the US draw closer.