Why Is Putin Traveling to Vietnam?

President Vladimir V. Putin of Russia wrapped up a state visit to a longtime partner, North Korea, and moved on to another, Vietnam, arriving early Thursday local time hoping to shore up crucial partnerships in the region as he wages a protracted war in Ukraine.

Mr. Putin’s war in Ukraine has left him isolated from the West, and his need for munitions to fight that war has pushed him closer to North Korea and its leader, Kim Jong-un. The two leaders have bonded over their common historical opponent, the United States, and on Wednesday revived a Cold War-era mutual defense pledge between their nations.

In Vietnam, by contrast, Mr. Putin — who landed in Hanoi, according to Russian state media — will meet with officials who have recently forged deeper bonds with Washington. But Moscow has long been Hanoi’s main source of weapons, and Mr. Putin is keen to hold on to that position.

It is Mr. Putin’s fifth visit to Vietnam and follows trips last year by President Biden and President Xi Jinping of China, two leaders who sought assurances from Hanoi that it was not taking the other’s side.

For Vietnam, Mr. Putin’s trip will be an opportunity to solidify ties with Russia, its most important defense partner. Even though it has upgraded relations with the United States, Vietnam was still looking for secret ways last year to purchase Russian military equipment in contravention of American sanctions.

Washington has rebuked Hanoi for inviting the Russian leader, saying, “No country should give Putin a platform to promote his war of aggression and otherwise allow him to normalize his atrocities.”

This week, Vietnam’s newly installed president, To Lam, told the local Russian envoy that Hanoi “always considers Russia one of the top priority partners in its foreign policy.”

Here’s what to know about relations between Moscow and Hanoi.

Russia and Vietnam have deep military ties.

In 1950, the Soviet Union was among the first countries to give diplomatic recognition to what was then the Democratic Republic of Vietnam, or North Vietnam. Over decades, Moscow became Vietnam’s biggest donor, providing military aid when Hanoi was fighting its wars against France and the United States.

The defense relationship has underpinned many ties between the two countries, which over the years also shared communist ideology. Mr. Putin arrived in Vietnam with his new defense minister, Andrei R. Belousov, underscoring how security matters are central to the visit.

Russian equipment represents about 60 percent to 70 percent of Vietnam’s defense arsenal, according to Nguyen The Phuong, who studies Vietnam’s military affairs at the University of New South Wales in Australia. Russia has supplied Vietnam with coastal defense missile systems, six Kilo-class submarines, fighter jets and many more lethal weapons.

Nearly all of Vietnam’s naval vessels come from Russia, according to Mr. Phuong. Russia’s T-90 tanks, which were the last-known major purchase of Russian arms by Vietnam in 2016, form the backbone of Vietnam’s armored forces, he added. This means that Vietnam is still going to be reliant on Russia in the years to come.

Vietnam has looked beyond Russia for weapons.

But the imposition of Western sanctions on Moscow has increased concerns in Hanoi about Russia’s reliability as a supplier, and made it increasingly awkward for Vietnam to continue dealing with Russia as it engages with the West.

Many of Vietnam’s leaders are also aware of the Russian military’s struggles against Ukraine — footage has shown the T-90 tanks being blown apart by drones used by Ukraine. They are also cognizant of Russia’s deepening relationship with China, which they regard as a threat because of a longstanding territorial dispute in the South China Sea.

In recent months, it has turned to countries like South Korea, Japan and the Czech Republic as alternative sources of weapons. It has also tried to build up its own defense industry. It has looked to India, another former Soviet ally, to retrofit some of its weapons.

The United States has been actively offering more weapons to Vietnam, with senior officials traveling to the country in recent months. But analysts say the top echelons of Vietnam’s defense leadership remain suspicious of Washington. They are reluctant to tie their fate to a country where arms sales have to be passed through a Congress that could make the deal contingent on human rights.

The two nations have joint ventures in the oil business.

Russia has a significant stake in Vietnam’s lucrative oil and gas sector. Vietsovpetro, a joint venture run by Russia’s Zarubezhneft and Vietnam’s state-owned PetroVietnam, operates Vietnam’s largest oil field, Bach Ho.

The profits from Vietsovpetro have generated millions of dollars for both Russia and Vietnam. Zarubezhneft and Gazprom, another Russian state-owned energy firm, are also involved in oil exploration projects in Vietnam.

For Moscow, these projects come at a time when Russian oil and gas exports to Europe have plummeted following the imposition of sanctions from the European Union. But they have irked Beijing because they are in waters that it contends are part of its territory.

Before the coronavirus pandemic, Vietnam was also a particularly attractive destination for Russian tourists. In 2019, Russia sent the sixth-highest number of tourists of any nation to Vietnam, just after the United States. But the numbers dropped during the pandemic and fell further after Vietnam stopped direct flights in 2022 after Russia’s invasion of Ukraine. Direct flights resumed this year.

Mr. Putin is seen as popular with the Vietnamese brass.

Beginning in the 1950s, thousands of Vietnamese Communist Party officials, top business officials, doctors, teachers and soldiers were trained in the Soviet Union and Russia. That list includes the current party chief, Nguyen Phu Trong.

But some felt those deep ties were ignored by the last Soviet leader, Mikhail S. Gorbachev, and Russia’s first president, Boris N. Yeltsin.

“The Vietnamese feel that Gorbachev in the 1980s abandoned Vietnam in an effort to improve relations with China; Yeltsin, all through the 90s, barely paid any attention to Vietnam,” said Ian Storey, a senior fellow at the ISEAS-Yusof Ishak Institute in Singapore. “Once Putin was in power in 2000, he gave a lot of face to it. So the Vietnamese are grateful for that.”

He added that the Vietnamese leadership liked Mr. Putin because “he put Vietnam-Russia relations back on track.”

Paul Sonne and Damien Cave contributed reporting.