The international community should threaten Iran with “military sanctions” if the regime doesn’t stop pursuing its nuclear program, Prime Minister Benjamin Netanyahu said Wednesday, after another round of talks between six world super powers and Tehran ended without tangible progress.

“We have the problem of Iran that is continuing to defy the international community, [and] doesn’t seem to seek an end to its military nuclear program,” Netanyahu said during a meeting with Sri Lankan Foreign Minister G.L. Peiris in Jerusalem. “Like North Korea, it continues to defy all the international standards and I believe that this requires the international community to ratchet up its sanctions and make clear that if this continues there will be also a credible military sanction. I think no other means will make Iran obey the wishes of the international community.”

Earlier on Wednesday, a fourth round of negotiations between Iran and the five permanent members of the United Nations Security Council and Germany ended in Kazakhstan. The so-called P5+1 offered Tehran a “revised proposal, which we believe is balanced and a fair basis for constructive talks,” the European Union’s foreign policy chief, Catherine Ashton, said after the talks.

However, the meeting’s only concrete result was an agreement that technical experts from both sides will meet in Istanbul on March 18 and then again, with the P5+1 political officials, on April 5 in Kazakhstan.

US Secretary of State John Kerry said Wednesday the talks had been useful and left the door open for future bilateral talks between Washington and Tehran.

“Iran knows what it needs to do. The president has made clear his determination to implement his policy that Iran will not have a nuclear weapon,” Kerry said, according to Reuters.

UK Foreign Secretary William Hague said he looked forward to “further progress by experts in March on the revised and credible proposal” the P5+1 put to Iran.

“It is vital that progress is now made on addressing our most immediate concerns about Iran’s nuclear program,” Hague said. “Iran has much to gain from a diplomatic resolution to the nuclear issue and we are clear on the need for talks to deliver results.”

Hague said the most recent report by the International Atomic Energy Agency showed that Iran continues to expand its enrichment capacity and has failed to cooperate with its demands. Therefore, “Iran must show it is prepared to take the urgent action needed to address the international community’s serious concerns,” he said.

Earlier on Wednesday, new satellite images showed that an Iranian nuclear site that has been kept away from the inquiring eyes of UN inspectors is operational and apparently producing materials that could eventually be used to make an atomic bomb.

Fresh photographs of the Arak facility, published by Britain’s Daily Telegraph, indicate that heavy water production has commenced at the site, based on a cloud of vapor seen rising from a building there.

Amos Gilad, a senior Defense Ministry official, said that Israel had been well aware of the Arak facility for years, and that the new images did not indicate a dramatic change. The breathless new reporting was making it sound “like Iran has the bomb,” he said.

In fact, Iran does not have the bomb, Gilad said, but it is working to ensure that it has all the capabilities to attain a bomb the moment it takes a decision to get one.