Foreign ministers from the world's richest nations have held a two-day meeting in Liverpool, northwest England, seeking to present a strong, united front against global threats.
The G7 has warned that time was running out for Iran to agree a deal to curb its nuclear ambitions.
On Sunday – the second and final day of the meeting – foreign ministers from the world's richest nations also warned Russia about the consequences of invading Ukraine.
The gathering in Liverpool, northwest England, sought to present a strong, united front against global threats.
On Iran, G7 host Britain said resumed talks in Vienna were the Islamic Republic's "last chance to come to the negotiating table with a serious resolution".
"There is still time for Iran to come and agree this deal," Foreign Secretary Liz Truss told a news conference as talks wrapped up on Sunday.
Truss' comments are the first time a signatory to the original deal has given an ultimatum for the talks.
Negotiations restarted on Thursday to try to revive the 2015 deal between Iran and world powers, which the United States withdrew from under Donald Trump in 2018.
Iran claims it only wants to develop a civilian capability but Western powers say its stockpile of enriched uranium goes well beyond that, and could be used to develop a nuclear weapon.
US President Joe Biden has said he is ready to return to the agreement and Iranian officials maintain they are serious about committing to the talks.
But Western powers have accused Tehran of backsliding on progress made earlier this year and are playing for time.
In addition to Iran, the meeting also focused on Russia's build-up of troops on the border with Ukraine, given fears of a possible invasion of the former Soviet state.
Truss said there was "very much a united voice... that there will be massive consequences for Russia in the case of an incursion into Ukraine".
A senior US State Department official on Saturday said "a large number of democratic countries" were ready to join the G7 nations of Britain, Canada, France, Germany, Italy, Japan and the United States in taking action.
Biden earlier this week held a virtual summit with his Russian counterpart Vladimir Putin to voice Western concerns.
He is sending his top diplomat for Europe and Eurasian affairs to Kiev and Moscow next week to try to end the stand-off by diplomatic means.
Russia says the military build-up is a defensive measure against Ukraine moving closer to NATO.
Truss also said she and her counterparts were concerned about China's "coercive economic policies" and there was a need to counter them with their own initiatives as an alternative.