North Korea's Kim Jong Un expressed his "heartfelt thanks" to President Vladimir Putin, state media said Monday, as he headed home after nearly a week in Russia.Kim's tour of Russia's Far East, which began Tuesday, has sparked concern in the West that Pyongyang could provide Moscow with weapons for its war in Ukraine.During the trip, the North Korean leader inspected everything from Russian space rockets to submarines.

It also included a symbolic exchange of rifles with Putin.Pyongyang's Korean Central News Agency on Monday said Kim "extended his heartfelt thanks to President Putin and the Russian leadership" for "their special care and cordial hospitality" as he wrapped up the visit.Kim is heading home "after successfully completing the schedule of his official goodwill visit to the Russian Federation," KCNA said.He also wished "Russia prosperity and its people well-being," the KCNA report added.North Korea and Russia, long-standing allies, have both found themselves under far-reaching Western sanctions — Russia for its invasion of Ukraine and Pyongyang for its nuclear weapon tests.During his visit, Kim said his country would make bilateral ties with Russia its "number one priority," as he held a rare summit with Putin.Russia is eager for North Korea's stockpile of artillery shells to be used in Ukraine, while Pyongyang is looking for help with satellite technology and upgrading its Soviet-era military equipment, experts say.On Wednesday, Putin and Kim held talks at Russia's new Vostochny cosmodrome, located roughly 8,000 kilometers from Moscow.After the meeting, Putin talked up the prospect of greater cooperation with North Korea and the "possibilities" for military ties.But the Kremlin has said no agreement has or will be signed.Earlier Sunday, Kim watched a performing walrus at the Primorsky Aquarium, Russia's largest, accompanied by North Korean military officials.State media images showed Kim smiling as he applauded the walrus and its handler.Kim also "watched white dolphins and other sea animals performing acrobatic feats at the dolphinarium and looked around various places of the aquarium," KCNA said.The North Korean leader also praised the facility for "winning a reputation as a popular scientific research base" under Putin's leadership, it added.Kim's latest visit to Russia will "shine long in history", KCNA said, and will further consolidate the two countries' "militant unity" while "opening up a new chapter" of their relations.While meeting Kim, Putin accepted an invitation to visit North Korea and offered to send one of its nationals to space, which would be a first for the isolated country, as its own space program has struggled to develop.Kim is heading back to North Korea on his heavily armored train, with KCNA saying the leader "starts his way home after bringing about a new radical turn in the history of the development of the DPRK-Russia relations."DPRK is the acronym for North Korea's official name.Before departing from Vladivostok, the Pacific port city just over the border, Kim was presented with five explosive drones, a reconnaissance drone and a bulletproof vest as gifts from the governor of the Primorye region, which borders China and North Korea.