A staffer removes the Iranian flag from the stage after a group picture with foreign ministers and representatives of Unites States, Iran, China, Russia, Britain, Germany, France and the European Union during the Iran nuclear talks at Austria International Centre in Vienna, Austria on July 14, 2015.
CNN  — 

Biden administration officials on Thursday warned that the United States is prepared to turn to “other options” should diplomatic efforts to return to mutual compliance with the 2015 nuclear deal with Iran fail.

As negotiations resumed in Vienna, Austria, the administration also confirmed it will dispatch an interagency delegation to the United Arab Emirates as it seeks to tighten enforcement of Iran sanctions. The move comes as Tehran continues to develop its nuclear program and the negotiations aimed at salvaging the deal have so far faltered.

Secretary of Defense Lloyd Austin on Thursday said he was “deeply concerned about the Iranian government’s actions in recent months, both its continued provocations and its lack of constructive diplomatic engagement.”

Speaking alongside Israeli Defense Minister Benny Gantz in Washington, Austin vowed “to work closely with all of our partners throughout the region, including Israel first and foremost, to ensure that we are working together to address Iranian threats.”

“We will defend ourselves, we will defend our friends and we will defend our interests,” he said.

“The President has made clear that if diplomacy fails, we are prepared to turn to other options,” Austin said.

The administration has not specifically outlined what other measures it is considering should diplomatic efforts fail, but Secretary of State Antony Blinken did not explicitly rule out military options when he spoke alongside his Israeli counterpart in October.

Gantz, who also met with Blinken on Thursday, said he looked forward “to deepening our dialogue and cooperation vis-a-vis Iran, including the topics of joint military readiness to face Iran and to stop regional aggression and nuclear restoration.”

White House press secretary Jen Psaki said Thursday that “if diplomacy cannot get on track soon, and if Iran’s nuclear program continues to accelerate, then we will have no choice but to take additional measures to further restrict Iran’s revenue-producing sectors.” She did not elaborate on those measures.

Last week, US and European officials voiced public concern and frustration at Iran’s negotiating position, saying the new hardline Iranian government negotiators had sought to undo progress made in the previous six rounds of discussions. The talks, which were initially suspended last Friday, resumed Thursday.

The State Department said, however, that the US – which withdrew from the deal under the Trump administration and does not negotiate directly with Iran – will not return to Vienna until this weekend.

Delegation to be dispatched to UAE

Against the backdrop of faltering diplomatic efforts to revive the Joint Comprehensive Plan of Action, administration officials confirmed Thursday that the US is dispatching an interagency delegation, led by the top official in the Treasury Department’s Office of Foreign Assets Control, to the UAE as it moves to tighten enforcement of Iran sanctions.

State Department spokesperson Ned Price said the delegation would “focus on engagements with the private sector and key UAE government officials to discuss the private-sector companies and financial institutions that facilitate noncompliance Iranian commerce that runs through or in some way touches the UAE.”

Price said there would be “delegations to other partner countries in the coming weeks,” and he rebuffed the notion that the Biden administration had ever “looked the other way in terms of sanctions enforcement.”

“As new sanctions are applied, as bad actors attempt to circumvent sanctions, we always have to be adapting and tightening our sanctions enforcement to be one step ahead of those who would seek to circumvent them,” he said.

China, which is a party to the Iran nuclear deal, is the top importer of Iranian oil, despite US sanctions.

Price said there have been discussions with Chinese officials, “including at the senior-most levels