Russia has threatened to ban sales of a key rocket engine to the United States in response to new sanctions over the Skripal poisoning.

Sergei Ryabukhin, head of the budget committee in the upper house of parliament, called the measures announced by the state department late on Wednesday the “most obnoxious and cynical behaviour on the market” and said Russia has the means to respond if leader Vladimir Putin wishes to do so.

“The United States needs to finally understand that it's useless to fight with Russia, including with the help of sanctions,” he said.

He said Russia could in particular stop exports to the United States of the RD-180 rocket engine, which powers the first stage of the Atlas 5 rocket made by Boeing and Lockheed Martin.

Lawmakers in Washington had to partially roll back a 2014 ban on Russian engines in military and spy satellite launches due to US reliance on the RD-180.

Since its introduction in 2002, the Atlas 5 has carried the top-secret X-37B space plane, the New Horizons probe that flew by Pluto and the Curiosity rover that has been exploring the surface of Mars.

It is slated to take astronauts to the International Space Station in its first manned flight in 2019 following several delays.

Specialists search a refuge for homeless people in Salisbury in July after a two more people were poisoned by a Novichok nerve agent credit: Matt Dunham/AP

The Russian state-owned producer of the RD-180 said late last month it had signed a contract to deliver six more engines to the United States through 2020.

The new US sanctions will come into effect later this month and are designed to prevent Russian state companies from obtaining access to weapons, financial assistance or technologies related to US national security.

US officials have said they will cause hundreds of millions of dollars in losses and target electronic devices and engines, among other technologies.

They said a second round of even harsher sanctions would follow if Russia does not promise to stop targeting its citizens with chemical weapons, a pledge that Moscow is highly unlikely to make.

Mr Putin's spokesman said the sanctions were “absolutely illegal” and called it “categorically unacceptable” to link them to the Salisbury poisoning in March. He said Britain was ignoring Russia's calls for a joint investigation.

“Once again we deny in the strongest terms the accusations about the possible connection of the Russian state to what happened in Salisbury,” the spokesman said. “This is out of the question. Russia did not and does not have, and could not have, any connection to the use of chemical weapons.”

A Russian representative to the United Nations, Dmitry Polyansky, called the sanctions a “theatre of the absurd,” arguing that Washington had skipped gathering evidence to “blame everything on Russia, no matter how absurd and fake it is”.

The stock price of Russian state airline Aeroflot fell by 12 per cent on Thursday morning before regaining almost all of its losses. American media had reported the second round of sanctions could include a ban on Aeroflot flights to US destinations, but the American Chamber of Commerce in Russia and Russian officials dismissed this as unlikely.

The rouble has lost four per cent against the dollar since Wednesday.

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Moscow previously planned to cut off US sales of the RD-180 as part of legislation drafted in response to US sanctions in May over Russian interference in the 2016 presidential election.

The legislation, which would have also banned US software, medicine, tobacco and alcohol, was put on hold as Mr Putin geared up for a summit with Donald Trump in Helsinki in July.

Donald Trump backed Vladimir Putin's denial of interference instead of US intelligence findings at their meeting in Helsinki in July credit: Kevin Lamarque/Reuters

For now, the Atlas 5 still lacks an alternative to the Russian engine, but independent defence analyst Pavel Felgenhauer told the Telegraph that the United States has stockpiled enough RD-180s to continue launches for a few more years.

A ban on the engine's export “will hurt more the Russians who were planning to build some more of those engines,” he said.

“The space industry doesn't want (the ban) to happen but (members of parliament) from time to time are talking about it,” he added.

A British government spokesman praised the “strong international response to the use of a chemical weapon on the streets of Salisbury,” saying it “sends an unequivocal message to Russia that its provocative, reckless behaviour will not go unchallenged”.