Diplomats from Iran and world powers reconvened in Vienna on Tuesday to seek a deal reviving Tehran�s 2015 nuclear accord, with pressure mounting for results soon.

Negotiators from Iran and the remaining parties to the agreement � Britain, France, Germany, Russia and China � got back to work after a break of a little over a week to return to their capitals for consultations.

Officials say that the talks are reaching their final stage, though it�s unclear how long that might take. The negotiations have dragged on for months, punctuated by a long gap last year caused by the arrival of a hard-line new government in Iran. The current eighth round started just after Christmas.

The three Western European participants have been warning for a while that time is running out for a successful conclusion of the talks. They have argued that the accord will soon become an �empty shell� in light of Iran stepping up its nuclear program.

Iran insists that its program is peaceful.

On Friday, U.S. Secretary of State Antony Blinken signed several sanctions waivers related to Iran�s civilian nuclear activities. The move reverses the Trump administration�s decision to rescind them.

Iran�s foreign minister on Saturday welcomed the sanctions relief but called it insufficient.

In Beijing, Chinese Foreign Ministry spokesperson Zhao Lijian said Tuesday that the talks are �currently at a crucial juncture� and that all involved �should enhance the sense of urgency.�

�As the culprit in the Iranian nuclear crisis, the U.S. should thoroughly correct its wrong policy of maximum pressure on Iran and lift all illegal sanctions on Iran and third parties,� Zhao said. �On this basis, the Iranian side should resume full compliance.�

(AP)