Iran's remaining partners in the 2015 nuclear deal yesterday vowed to keep the energy exporter plugged into the global economy despite the US withdrawal and sanctions threat.

Three European nations along with Russia and China met with Iran to offer economic benefits and assurances that would lessen the blow of sweeping US sanctions, two months after President Donald Trump walked away from the landmark nuclear deal.

They said they remained committed to the 2015 accord and to building up economic relations with Iran, including "the continuation of Iran's export of oil and gas” and other energy products.

Theirforeign ministers agreed on an 11-point list of joint goals in Vienna, where the accord was signed three years ago with the aim of stopping Iran from building the atomic bomb in return for sanctions relief that promised greater trade and investment.

In the joint statement, Iran's Mohammad Javad Zarif and other top diplomats reconfirmed their commitment to the deal and its "economic dividends" for Iran, which has suffered worsening financial turbulence since Trump abandoned the accord.

Despite the US threat to penalise companies and banks that do business with Iran, the remaining signatories said they would work to promote investment and trade.

They also vowed to maintain financial channels, promote export credit cover and air, sea and overland transport links, and to work for the "the protection of companies from the extraterritorial effects of US sanctions".