BEIJING, May 23. /TASS/. The Chinese authorities have clearly signaled to the US that they will resolutely defend the interests of Chinese companies in response to unilateral American sanctions related to Russia and the Ukrainian crisis, Li Haidong, a professor at the China Foreign Affairs University, said.

"It is now clear that if the US sanctions and punishes Chinese companies using the Ukraine crisis as a pretext, China will resolutely defend its interests with countermeasures," he told the Global Times.

Previously, Beijing primarily expressed its principles through diplomatic language and declarations of its stance when responding to US sanctions, the expert said. "Now it is more resolute in implementing specific actions," he stressed.

China's countermeasures "clearly highlight the extreme absurdity of US actions amid the Russia-Ukraine conflict against Chinese firms," Li said. "With the countermeasures, it is hoped that the US will stop harming China's national interests and the legitimate rights of Chinese enterprises," he noted.

"The countermeasures are quite strong and are defensive in nature. They aim to safeguard our sovereignty and national security and target the inappropriate actions of the US that involve long-arm jurisdiction over China and infringe upon China's sovereignty," the expert said.

The countermeasures targets are "the stubborn, irrational anti-China extremists in the US and US companies that violate China's sovereignty and dignity," he said "The countermeasures will remind US politicians and business entities that they cannot expect to profit and gain political capital by infringing on China's interests," Li added.

The Chinese Foreign Ministry said on Wednesday that the Chinese authorities had taken measures against 12 companies of the US military-industrial complex and 10 senior US officials due to US sanctions against Chinese enterprises associated with Russia. The decision to impose retaliatory measures by China came into force on the same day. Among the blacklisted companies were Lockheed Martin Missiles and Fire Control, Lockheed Martin Aeronautics, Javelin Joint Venture, Raytheon Missiles, General Dynamics Ordnance and Tactical Systems, General Dynamics Information Technology, General Dynamics Mission Systems, Intercoastal Electronics, System Studies and Simulation, Iron Mountain Solutions, Applied Technology Group and Arcient.