Russian Su-35 fighter jet (File Photo)

Russia is believed to have supplied the first batch of four Su-35 fighters to China.

According to a Russian web resource, Komcity, “In accordance with the signed contract earlier this year, the first batch of jet aircraft originally planned to deliver to China after the New Year, but the Russian side agreed to accelerate the transfer of aircraft and appointed deadline December 25th.”

Fligthradar24.com recorded the flight path of IL-76 transport aircraft from Komsomolsk-on-Amur aircraft building plant (manufacturer of Su-35 planes) to the military airfield near Cangzhou Cang County ( Hebei province), which is one of the training and testing bases of the PLA Air Force on December 25.

Earlier this month, Tass reported that Russia will provide to China the first batch of four Sukhoi-35 jets by December 25 quoting an unnamed source within the system of military-technical cooperation.

In November 2015 Russia and China concluded a contract for 24 Sukhoi-35 fighters. Under the $2 billion deal Russia is also to provide ground equipment and spare engines.

The new Su-35s will be fitted with onboard readout systems that display data in Russian language. Russia will configure the onboard systems of the military aircraft the same way as that of aircraft it supplies to the country's own Aerospace Forces. Hence, as the Su-35 aircraft will be fitted with BeiDou onboard navigation system modules, all of the planes’ readout systems will be displaying data in Russian.

The Chinese Su-35 will receive newest Irbis-E systems, which provide detection, tracking and coordinate measurement of air, ground, and surface targets, day-and-night, in all weather conditions in the presence of natural noise and jamming.

The fighters also get the RSUO weapon management system, which has special-purpose hardware to identify the condition of weapons aboard the aircraft and control their loading management.

Among other systems – an electronic countermeasures release system that provides protection for the jet from "air-to-air" guided missiles and ground-launched missiles with the help of interference cartridges, a set of flight control levers and sticks for the aircraft and its engines based on HOTAS, which operates by forming analog, manual control signals and issuing single commands, and a SAP active jamming station.