 Risk of Russian tactical nuclear strike? Higher than thought. Russia's threshold for using shorter-range tactical nuclear weapons may be lower than defence experts in the West believe. The Financial Times has claimed cited purported Russian military documents. The materials, which were allegedly presentations for Russian naval officers, discussed operating principles for the use of nuclear weapons the Financial Times reported. They were supposedly produced between 2008 and 2014 and shared with the British outlet by Western sources. Kremlin spokesman Dmitry Peskov told the newspaper that Russia strongly doubts the authenticity of the documents. Moscow's military doctrine allows for the deployment of nuclear weapons in retaliation to a first strike against it or its allies or in situations where Russian statehood is threatened. Nuclear officials, including President Vladimir Putin, have drawn attention to the country's nuclear arsenal amid the Ukraine conflict. The US and its allies have accused the Russian leader of nuclear blackmail, although Moscow has rejected that allegation. The criteria for the use of nuclear weapons in the documents reviewed by the FT included losses by Russian forces that, would irrevocably, lead to their failure to stop major enemy aggression and a critical situation for the state security of Russia. The destruction of 20% of Russia's strategic missile submarines, 30% of nuclear-powered attack submarines or a simultaneous hit on main and reserve coastal command centres were cited as specific examples. France insists on sending Western troops to Ukraine, Russia promises catastrophic scenario. The Elishe Palace, after French President Emmanuel Macron's statement about the possibility of sending troops from Western powers to Ukraine, insists that Kyiv's allies should discuss this issue. As the source explained to CNN with his statements, Macron signalled his Russian counterpart, Vladimir Putin, about his determination and desire of France to prevent any victory of the full-scale Russian invasion. The source stressed that the French president did not talk about the actual departure of troops and no decision was made on this, but there are all sorts of things that were ruled out two years ago and which are no longer ruled out. Macron has not ruled out the possibility of sending Western troops to Ukraine in the future after a meeting in Paris emphasising that there is currently no consensus among allies. A number of European states and NATO have since stated that they do not plan to send any troops to Ukraine. The potential deployment of NATO troops to Ukraine will lead to a catastrophic scenario and could be interpreted as a declaration of war on Moscow, top Russian Senator Konstantin Kossachev has said. The vice-speaker of Russia's upper chamber, the Federation Council, offered his take on remarks by French President Emmanuel Macron on the possibility of sending troops in a telegram post. The approach exhibited by the French leader carries a risk of the situation developing into a catastrophic scenario, Kossachev warned, stating that the move would not be tolerated by the Kremlin. This is the line beyond which it's no longer just NATO's involvement in the war. This has been happening for a long time but can be interpreted as the Alliance entering direct hostilities or even as a declaration of war, Kossachev wrote. The senator's comments echoed a statement made by Kremlin spokesman Dmitry Peskov who said the move would make a direct collision between the U.S.-led bloc and Moscow not only possible but actually inevitable. U.S. struck Houthi cruise missiles and drones in Yemen. The U.S. has launched a series of strikes against Houthi cruise missiles and surface drones in Yemen according to the U.S. Central Command. The U.S. Central Command sent comm forces conducted seven self-defense strikes against four Houthi unmanned surface vessels and seven mobile anti-ship cruise missiles that were prepared to launch against ships in the Red Sea, the U.S. Central Command said. It is reported that the U.S. military detected these missiles and unmanned surface vessels in Houthi-controlled areas of Yemen and determined they presented an imminent threat to U.S. Navy ships and merchant vessels in the region. These actions will protect freedom of navigation and make international waters safer and more secure for U.S. Navy and merchant vessels. Since November of last year, there have been ongoing attacks by Yemeni Houthis on trade ships in the Red Sea, often associated with Israel. In January, the terrorist group launched its most significant attack. The U.S. and British military repelled an attack in the Red Sea in early January. At the beginning of January, the U.S. and Britain conducted powerful strikes against Houthi-related targets in Yemen. This was in response to the constant attacks by the Houthis on civilian ships in the Red Sea. On January the 28th, a Houthi drone in the Red Sea attacked a British military ship and the next day the Yemeni Houthis claimed to have attacked an American destroyer. However, the Pentagon refuted the militants' claim. Also on February the 6th, it was reported that a British cargo ship was attacked by the Houthis in the Red Sea.