A new nuclear deal must be agreed on for Iran to reign in its ballistic missile programme, German Foreign Minister Heiko Maas said on Saturday.
He told Spiegel magazine that an accord to limit Tehran's nuclear prowess was needed "because we distrust Iran".
"A form of 'nuclear agreement plus' is needed, which also lies in our interest," said Mr Maas, whose country currently holds the European Union presidency.
"We have clear expectations for Iran: no nuclear weapons, but also no ballistic rocket programme which threatens the whole region. Iran must also play another role in the region."
"We need this accord because we distrust Iran," he added.
The 2015 nuclear deal – known formally as the Joint Comprehensive Plan of Action, or JCPOA – gave Iran relief from sanctions in return for curbs on its nuclear programme.
The European Union and the United States were the main signatories in the deal, but US President Donald Trump unilaterally withdrew from the accord in 2018 and has reimposed crippling sanctions on Tehran as part of a "maximum pressure" campaign.
President-elect Joe Biden has signalled that Washington could rejoin the deal as a starting point for follow-on negotiations if Iran returned to compliance.
But Iranian Foreign Minister Mohammad Javad Zarif has rejected talk of reopening the 2015 deal, saying on Thursday: "We will not renegotiate a deal that we negotiated."
He added that Western powers should look to their own behaviour before criticising Iran and that they must honour the 2015 deal.