Since Mr. Trump became the U.S. president, the United States' relation with Iran has descended into a vicious circle. In May last year, President Trump withdrew from the Iran nuclear deal, known as the Joint Comprehensive Plan of Action (JCPOA), and re-imposed the “highest level of sanctions” against Iran.

During the past year, the United States, manipulating its economic strength and its dominant position in the international financial sector, has tried hard to completely block Iran from the sector and trade with other countries through "secondary sanctions."

The U.S. intention was to compel Iran to submit to the U.S. demands, which required Iran not only to abandon its nuclear program and its ballistic missile program, but also to give up its support to the international and regional "terrorist groups" and stop threatening U.S. regional allies.

Although the U.S. “maximum pressure of campaign” has seriously crippled the Iranian economy, it has failed to achieve what it wanted from Iran.

It is worth noticing that, under pressure from the United States, Iran has excised “strategic restraint” in responding to U.S. exit from the JCPOA. Nowadays, Iran regard the Iranian nuclear deal more from the political and security perspectives, rather than purely economic interests.

The Rouhani government believed that as long as the European countries are still committed to preserving the Iranian nuclear deal, Iran could drive a wedge between the Europeans and Americans, which in turn could minimize the severe pressure from the U.S. and improve the Iranian political and security environment.

But so far, the European countries have failed to transform their political commitment into concrete economic benefits. The increasing U.S. pressure coupled with the Europeans' hesitation has inflamed the internal struggle between moderates and hardliners within Iran over how Iran should respond to the pressure.

Hardliners argued that the Rouhani government's weak response to the U.S. would only encourage the latter to put greater pressure on Iran. They demanded that if it is not benefiting from the Iran nuclear deal, Iran should also quit the deal and resume large-scale uranium enrichment.

So far, the Rouhani government still has the support of supreme leader Ali Khamenei, but its position with regard to the nuclear deal became tougher. Iran has repeatedly warned the Europeans that its patience has run out.

Recently, the tension between the U.S. and Iran has intensified, as the U.S., stepping up its "campaign of maximum pressure," has taken a number of new provocative measures, such as designating the Iranian Revolutionary Guards Corps（IRGC）as the "foreign terrorist organization" and ending sanctions waiver to import Iranian oil.

But the most critical was the Trump administration revoking two sanctions, which doesn't allow Iran to export its extra enriched uranium and relating to heavy water, waivers prohibiting Iran's civilian nuclear cooperation with other countries on May 3.

Under these sanctions, Iran would only have two choices: one is Iran has to give up its Inalienable rights of uranium enrichment; another is that Iran will eventually exceed limits set by the nuclear deal, and as a result, Iran will be regarded as a violation of the nuclear deal.

Therefore, Iran has to take some countermeasures. On May 8, Iranian President Rouhani announced that Iran would stop selling stockpiles of enriched uranium and heavy water for 60 days.

If by the end of 60 days, the Iranian economic interests will not be safeguarded, the country will resume enriching uranium exceeding the limits of purity level of 3.67 percent, and this means Iran's end with the JCPOA.

The Iran nuclear deal is widely seen as the last barrier against a massive military conflict between the United States and Iran. At this time, the cloud of war is gradually gathering over the Persian Gulf.

Once Iran is also forced to withdraw from the nuclear deal and start to resume large-scale uranium enrichment activities, there will be a high risk of a large-scale military conflict in the Middle East, the result of which will not only lead to more volatility in the Middle East, causing a massive humanitarian crisis, but have a great negative impact on world peace and stability and global economic development, and on global nuclear non-proliferation as well.

Therefore, the international community has expressed general concern about the prospects for the "Iran nuclear deal."