Washington’s unilateral slapping of sanctions on Iran not only hampers the negotiation process, it runs counter to international law, says the Russian Foreign Ministry.

­Moscow has called the latest round of restrictions against Tehran inadmissible.

"In connection with the American administration's decision to tighten sanctions against Iran, which impacts companies from third countries cooperating with Iran in the oil and oil-refining industry, and in the banking sector, we reiterate that Russia views such extra-territorial measures as unacceptable and against international law," Foreign Ministry Deputy Spokesperson Maria Zakharova told reporters on Tuesday.

By resorting to such provocative measures, the US is hampering meaningful talks with Tehran, Moscow insists.

"Such a practice seriously obstructs advancement toward a constructive dialogue with Tehran,” Zakharova said. “Stronger sanction pressure, which some of our partners see almost as a goal in itself, will not encourage Iran to sit down at the negotiating table.”

The practice of tightening sanctions has gone beyond the tasks of preventing proliferation in Iran's nuclear program, the spokesperson added.

The Russian Foreign Ministry was responding to remarks made by Hillary Clinton, US Secretary of State, who told a press conference in Washington that Iran poses a money-laundering threat.

"The US Treasury Department is formally identifying Iran as a jurisdiction of primary money-laundering concern,” Clinton, with Treasury Secretary Timothy Geithner behind her, told reporters. “This is the strongest official warning we can give that any transaction with Iran poses serious risks of deception or diversion.”

Clinton then warned of “increasingly aggressive measures” against the Islamic Republic “unless Iran's leaders decide to change course and meet their international obligations.”

The expanded sanctions blacklist 11 organizations, thought to be aiding the development of Iran’s nuclear program, which Tehran says is meant for peaceful purposes including power generation. Other parts of the sanctions target companies that aid Iran’s oil and petrochemical industries.

US media reported that Clinton phoned Israeli Prime Minister Benjamin Netanyahu Monday evening to brief him on the new measures. Their conversation came after the US had warned Israel of the risk of “unintended consequences” should Israel attempt a military assault on Iran in an effort to destroy its nuclear facilities.

Meanwhile, Iran dismissed the new sanctions, saying they will not damage the economy.

"Such measures are condemned by our people and will have no impact and be in vain," Iranian Foreign Ministry spokesman Ramin Mehmanparast told a news conference Tuesday.

The United Nations has passed four rounds of global sanctions against Iran since 2006.

Robert Bridge, RT