President Donald Trump has said he wants to achieve "world peace," but his rejection of the Obama-era nuclear deal may only lead to more conflict with Iran.
Prices could reach $90 a barrel.
On Sunday, the Iranian rial reached a record nadir in street trading.
The Russian government hit back on sanctions by taking Western cheese, fruit and foodstuffs, only to bulldozer them at the border.
A bipartisan bill wants to halt the possibility of returning to business as usual with the Kremlin, instead asking for a report on Putin's finances and those of his close associates.
"It's absolutely clear that Russia needs to do more," a State Department official said after a report that Russia has issued 700 new work permits this year.
Two former State Department officials who helped craft the 2015 Iran nuclear deal say allies are increasingly frustrated with U.S. financial dominance—and this may be the final straw.
"Don't play with fire, or you will regret."
"You impose sanctions on major producers ... and yet you are asking them to reduce the prices?"
Although Russia's elite may be holding onto their wealth despite U.S.-led efforts to target the economy, the working class and poorer communities may not be faring so well.
Meanwhile, Russia's Ministry of Economic Development has put forward amendments to federal law that would allow companies to hide information about some public contracts.
The U.S. government added three Russians and five companies said to be linked to Moscow's security forces.
"North Korea can build nukes and ICBMs, but claim they are too poor to pay for foreign travel costs," a Korea expert said.
Russia's Putin has visited China at least once a year since relations with the West collapsed over his annexation of Crimea in 2014.
Russian President Vladimir Putin said that without "trust," Moscow and Washington may resort to "force," and "this might lead to tragedy."
"He made us realize that if you need a helping hand, you will find one at the end of your arm," wrote Donald Tusk, president of the European Council.
U.S. Secretary of State Mike Pompeo said the Trump administration was open to lifting sanctions and allowing private American investments into the reclusive state.