No doubt these conflicts have contributed to Blix’s conclusion that he is “not all that confident” that the diplomatic process will succeed, although he also said in the interview that he hopes for resolution and that it would be good for all parties. Conversely, Blix said, if the talks continue to deteriorate and ultimately fail, “there is an increased risk for all.”

Although some critics of the talks have described US President Barack Obama as being so desperate for a deal that he will give away as many concessions as it takes, it seems likely that the chances of a final agreement will be damaged by serious indications that Iran cannot be trusted to follow through on a deal.

Naturally, the strongest opponents of the Iranian regime believe that the very nature of that regime is reason enough to doubt its commitment. But Reuters reported on Thursday that Britain had arguably presented the latest concrete evidence of this to a panel monitoring Iran’s compliance with international sanctions.

“The UK government informed the Panel on 20 April 2015 that it ‘is aware of an active Iranian nuclear procurement network which has been associated with Iran’s Centrifuge Technology Company (TESA) and Kalay Electric Company (KEC),” said the Panel of Experts. The two firms are blacklisted by the UN due to connections with Iran’s banned nuclear activities.

Regardless of these latest allegations, several members of the UN panel came to the conclusion that Iran’s existing techniques for circumventing international sanctions have been continuing unchanged. This assessment contradicts Iranian Foreign Minister Mohammad Javad Zarif’s claim in an NYU speech on Wednesday that the Iranian government was fulfilling all of its obligations for the sake of a final agreement, and that the US was not doing so by virtue of its continued enforcement of existing sanctions.

In addition to this enforcement, the US has also reportedly been pressing its Asian allies to refrain from raising their imports from Iran, noting that the nuclear agreement and the end of sanctions are by no means foregone conclusions. This has apparently been working on the whole, although some countries including South Korea and Japan have increased their imports of Iranian oil in the past year.

Still, the Indian government’s responsiveness to US requests has helped to create a situation in which Iran’s exports of oil to Asian countries fell 9.2 percent in March, relative to the same period last year, according to Money Control. This continued economic pressure increases the need for sanctions evasion in other areas, from the Iranian perspective. It also constitutes Western leverage that opponents of the nuclear negotiations fear will be lost if sanctions relief continues to be portioned out to the regime in absence of a truly satisfactory nuclear deal.