Russian Energy Minister Alexander Novak said on Tuesday that Iran is not the cause of instability in the Persian Gulf and that sanctions against the country are “unlawful”.

“As regards restrictions on Iranian exports, we support Iran and we believe that the sanctions are unlawful; they have not been approved by the UN,” Novak told CNBC.

He added that he didn’t think Iran should be considered as the cause of the unstable situation in the region.

“These steps seriously destabilize the situation, not only in Iran, upon whom the sanctions have been imposed, but, as we can all see, in the entire region around the Persian Gulf,” he said.

Tension between Tehran and Washington has increased since Trump withdrew the U.S. from the 2015 nuclear deal in May 2018 and introduced harsh sanctions against Iran.

Tensions entered a new stage since April when the U.S. designated the IRGC (part of the Iranian military) as a terrorist organization, announced that it does no renew waivers for the eight major buyers of the Iranian oil, and started beefing up its military presence in the region, particularly in the Persian Gulf.

On Saturday, the U.S. deployed F-22 stealth fighters to Qatar for the first time, adding to a buildup of U.S. forces in the Persian Gulf amid tensions with Iran.

The tension started rising after the Iranian military shot down an unmanned U.S. surveillance drone on June 20 after it breached Iran’s airspace. The U.S. drone entered the Iranian airspace from the United Arab Emirates (UAE).

Russia’s top diplomat has also blamed the U.S. for Iran’s uranium stockpile surpassing the 300 kilogram limit set by the 2015 nuclear deal.

“Iran’s decision to surpass the uranium stockpile limit was caused by U.S. sanctions,” Fars news agency quoted Sergey Lavrov as saying on Tuesday.

He noted that the sanctions have prevented Iran from selling the excess uranium it produces, contributing to its stockpiling.

Russian Deputy Foreign Minister Sergei Ryabkov on Monday spoke in the same vein. "It should be understood as the natural consequence of the events, which have gone before,” Ryabkov said of Iran’s stockpile surpassing the limit.