U.S. Secretary of State Mike Pompeo in a series of tweets on June 28, kept the pressure on Iran, both on the issue of nuclear weapons and Iran’s policies in the region.

First, came a tweet by Pompeo on the 50th anniversary of the Nuclear Non-Proliferation Treaty, saying, “we must renew our efforts to reduce the dangers posed by nuclear proliferation, including confronting immediate challenges from DPRK and Iran”.

Immediately, another tweet followed, in which the secretary of state argued that the nuclear deal with Iran did not deter that country from “nuclear ambitions”. “U.S. seeks an arrangement that permanently prevents Iran from being able to develop or acquire nuclear weapons, or the ballistic missiles to deliver them”, he added.

But what was perhaps more direct, was his tweet later in the day, addressing Iran’s policies in the region. Noting that Iran’s support for Yemen’s Houthis endangers Saudi Arabia and the U.A.E., Pompeo pointed the finger at Iran’s Supreme Leader. “Ayatollah Khamenei must be held accountable for destabilizing Gulf's security & prolonging suffering of the Yemeni people.”

President Donald Trump’s administration insists that not only Iran’s nuclear ambitions are a serious cause for concern, but also the regional policies it pursues, interfering in Syria, Yemen and Iraq are unacceptable.

By withdrawing from the Comprehensive Plan of Action or JCPOA, as the 2015 nuclear deal is called, the administration has strongly linked its decision to Iran’s “unacceptable” behavior in the region.

An unnamed U.S. official told reporters on June 26 that the U.S. will be putting pressure on other countries to stop their oil purchases from Iran, as new sanctions are set to kick in in November.