Talks on the Iranian nuclear program continued at a low level Tuesday, even as prospects for a peaceful outcome grow increasingly grim.

Senior-level, US-led negotiations to win guarantees that Iran does not seek nuclear weapons have foundered. Meanwhile, there are disturbing developments. Concern is running high that last week’s suicide bombing attack on Israeli civilians in Bulgaria could signal a significant escalation in the covert war between Israel and Iran. The debacle in Syria may threaten Iran’s umbilical-cord relationship with Hezbollah, something which would have unforeseen consequences in the Middle East.

And yet, with all this going on, and after the senior-level talks broke down in Moscow in June, deputies to the European Union and Iranian negotiators met Tuesday in Istanbul. The EU deputy is Helga Schmid, who works for the Union’s foreign policy representative, Catherine Ashton. Ashton speaks for the six powers negotiating with Iran, the United States, Russia, China, Britain, France and Germany. Ali Bagheri, meanwhile, is the deputy to Iran’s head nuclear negotiator Saeed Jalili. Their meeting followed an experts session on July 3, also in Istanbul, which was dedicated to making clear the details of the positions of the two sides. EU officials refused to comment on the Bagheri-Schmid meeting. But they said it would be followed by “contact” between Ashton and Jalili, which means that the two could meet in person or just talk by phone.

After this, there will probably be another experts meeting, rather than talks at a senior foreign ministry level. The experts gathering on July 3 took 13 hours and was judged fruitful enough for diplomats to say that another such experts meeting was likely to take place, although one has not yet been scheduled. “The last round of experts was sufficient to continue the process,” a diplomat close to the talks told me.

Diplomats said the bilateral meetings and experts talks will not be affected by the dramatic developments in Bulgaria and Syria, or even what happens in Vienna where the UN watchdog International Atomic Energy Agency (IAEA) is stymied in its investigation of Iran’s nuclear program.

They said there was a real desire to keep the dual-track going of openness to talks coupled with pressure on Iran to get it to cooperate with the IAEA and to rein in its nuclear work. The ongoing negotiations are the only forum where the Iranians are talking at a political level to the international community about their nuclear ambitions. They are the latest stage in a diplomatic process which began in 2003, after Iran was discovered hiding almost two decades of nuclear work.

Other avenues for peaceful resolution are also foundering. Parallel to the official government contacts is something called Track 2 diplomacy, in which non-governmental groups and former government officials try to establish dialog which can hopefully lead to official give-and-take between the two sides. The virtue of Track 2 is that it is often off-the-record, backdoor diplomacy in which new approaches can be tried. But this important channel seems to have dried up over the past year.

The US tactic at this point is to hang tough, since Washington mistrusts Iran and wants to see concrete progress before making compromises of its own. The United States insists that Iran stop, as a confidence-building measure, enriching uranium to 20 percent enrichment, which is closer to weapon-grade. Iran started last year to enrich to 20 percent to fuel a research reactor which makes medical isotopes. The bulk of Iran’s program, however, is designed to enrich to up to 5 percent to make what can be fuel for civilian power reactors. The US position is that Iran will only get relief from the tough sanctions now in effect when it makes concessions on enrichment in general. The United States wants Iran to honor UN Security Council calls for it to suspend all enrichment work, which the United States fears could be eventually used to refine weapon-grade uranium of over 90 percent enrichment.

Iran however refuses to suspend and insists that its right to enrich be acknowledged as “inalienable” under the nuclear Non-Proliferation Treaty. It has raised the possibility of needing to make fuel for a nuclear submarine development program, which could require enrichment of around 60 percent. In any case, Iran calls for sanctions to be lifted as a first step, not a later one. The Islamic Republic says that the IAEA, after years of investigation, has no proof that it seeks nuclear weapons.

It is a stand-off. The political talks have failed at this point because the two sides were no closer to an agreement despite having improved the nature of their dialog by avoiding rants and rhetoric. The experts talks which are continuing are more than a lifeline. They are all that is left after a decade of official and unofficial contacts to defuse a face-off which could lead to war.

Whether they can go further at a low-boil that will allow for secret US-Iranian talks, which many feel is the only way to end this crisis, is unclear. What is certain is that both sides are keeping open a very significant line of communication. It is not a case of the medium being more than the message. The hope is that the medium can become a vehicle for messaging. Whether that can happen amidst growing regional tension, Iran expanding its nuclear work, and with presidential elections this year in the United States and next year in Iran is an open question.