Germany's foreign minister says Europe will this week respond to Iran's pledge not to abide by the 2015 nuclear deal.
The three leaders issued a joint statement saying there was "an urgent need for de-escalation" and that the "current cycle of violence in Iraq must end."
The trio reiterated their "attachment to the sovereignty and security of Iraq," saying that "another crisis risks jeopardizing years of efforts to stabilize Iraq."
Fighting against Islamic State in the region "remains a high priority," the statement added. It urged Iraqi authorities to continue providing support to the US-led alliance fighting the militant group after Iraq voted to expel foreign troops linked to coalition forces fighting IS.
The joint statement came as German Foreign Minister, Heiko Maas on Monday morning branded US threats of sanctions against Iraq in response to voting to oust US troops as "not very helpful."
"I don't think it works to convince Iraq with threats but with arguments," said Maas, talking to Germany's Deutschlandfunk public radio.