Kim Jong-un sent a special envoy to Russia to ask Putin to sell him Su-35 fighter jets.

North Korea’s Kim Jong-un sent a special envoy to Moscow to ask Russia to sell him its most advanced fighter jets, South Korean and Russian media are reporting.

On Thursday, a senior South Korean military official told JoongAng Ilbo , a conservative South Korean daily newspaper, that North Korea officially asked Russia to sell it the Sukhoi Su-35 fighter jet. Notably, the Russian state-owned ITAR-TASS news agency picked up the JoongAng Ilbo report on its website on Friday.

According to the original report, the request was made in November when Choe Ryong-hae, North Korea’s number two, traveled to Russia as Kim Jong-un’s special envoy. During the trip, Choe met with Vladimir Putin and gave the Russian president a letter from Kim.

“Choe Ryong-hae, who visited Moscow as a special envoy of North Korean leader Kim Jong-un in November last year, asked Russian President Vladimir Putin to provide Sukhoi Su-35 fighter jets,” JoongAng Ilbo quoted the military source as saying. The source added that he didn’t believe Russia would consent to the sale because of international sanctions against North Korea.

(Recommended: 5 Russian Weapons of War NATO Should Fear)

As Dave Majumdar wrote in The National Interest last month, the Su-35 “is the most potent fighter currently in operation with the Russian Air Force. The powerful twin-engine fighter, which is an advanced derivative of the original Soviet-era Su-27, is high flying, fast and carries an enormous payload. That, combined with its advanced suite of avionics, makes the Su-35 an extremely dangerous foe to any U.S. fighter, with the exception of the stealthy Lockheed Martin F-22 Raptor.”

The 4++ generation fighter jet would be a substantial upgrade over the North Korean Air Force’s current arsenal, which mostly consists of outdated Chinese and Russian platforms like the MiG-21 and Su-25. North Korea purchased these aircraft from Russia in the waning days of the Soviet Union.

North Korea has long sought more modernized aircraft to compete with the South Korean and American fleets. However, as the military source told JoongAng Ilbo, “The North produces many weapons systems domestically, but it appears to have sought Russia’s help because building fighter jets requires more complex technologies.”

(Recommended: 5 Weapons Russia Could Use in An Arctic War)

It’s not the first time that North Korea has gone abroad in search of more modernized fighters. Kim Jong-un’s father and predecessor, Kim Jong-Il, asked Russia to sell it advanced fighter aircraft during summits in 2001 and 2002. Kim Jong-Il returned to Moscow in 2011 to again ask Russia to sell it fighter jets. That same year, the former North Korean leader also traveled to Beijing to ask then-Chinese President Hu Jintao to sell North Korea J-10 and J-11 stealth fighters. Hu rejected the request.

(Recommended: 5 North Korean Weapons of War S. Korea Should Fear)

Even if Russia won’t sell Pyongyang the Su-35, Moscow has shown an interest in strengthening ties to the Hermit Kingdom in recent months. Last month, a Kremlin spokesperson announced that Putin has invited Kim Jong-un to Moscow in May of this year to celebrate the 70 anniversary of Nazi Germany’s defeat. If Kim accepts the invitation, it would be his first trip abroad since taking over power in North Korea following his father’s death in late 2011.

Zachary Keck is the managing editor of The National Interest. You can find him on Twitter: @ZacharyKeck .