BELGRADE, Serbia

Latvian President Edgars Rinkevics, speaking at a summit of nine countries on NATO's eastern flank, also known as the Bucharest Nine (B9), urged NATO members to spend 2% of their GDP on defense.

The one-day B9 summit was held on Tuesday in the Latvian capital of Riga.

The summit was one of several events marking NATO's 75th anniversary and Latvia's 20th anniversary as a NATO member.

"We agreed at the Washington summit to further strengthen NATO's deterrence and defense posture. We also expect the heads of state to continue to improve the region's defense plans.

"We also quite intensely discussed during the summit that leaders of ally countries should insist that all member states abide by the threshold of defense spending GDP," Rinkevics said in a joint press conference with other leaders, following his speech at the summit.

He added that long-term support for Ukraine is also on the agenda.

Leaders from Bulgaria, the Czech Republic, Estonia, Lithuania, Poland, Romania, and Slovakia have attended the B9 summit, Latvia's first to host.

Polish President Andrzej Duda, for his part, expressed satisfaction with Sweden and Finland's participation in the summit.

"This is living proof that NATO's open door principle is working, as new countries join. This is a huge benefit," Duda said.

Despite not being members of NATO's eastern flank, Finnish President Alexander Stubb, Prime Minister Petteri Orpo, and Swedish President Ulf Kristersson all attended the summit.

NATO Secretary-General Jens Stoltenberg, for his part, said at the joint press conference that B9 discussed important issues, including preparations for the upcoming NATO summit in Washington and how to increase support for Ukraine.

"The B9 countries play a critical role in NATO's strengthening deterrence and defense," Stoltenberg said.

He added that since 2014, NATO has carried out the most extensive enforcement in a generation since the Cold War.

"At the NATO summit, I expected allies will make decisions to strengthen deterrence and defense, including agreeing to a significant role for NATO in coordinating training equipment for Ukraine and committing to a long-term financial pledge," he said.

The summit did not issue a joint declaration after its conclusion, as is customary, because Hungarian President Tamas Sulyok did not attend.

Instead, a statement was issued in the name of Latvian, Romanian and Polish presidents, who co-hosted the Riga gathering.

The statement reaffirmed the member countries' unwavering commitment to Ukraine's independence, sovereignty, and territorial integrity within its internationally recognized borders.

"This is the only way to restore peace and rule-based order in Europe. We condemn in the strongest possible terms the unjustified and illegal brutal war against Ukraine," said the joint statement, issued on behalf of other B9 leaders.

The members also expressed satisfaction with the new members of the alliance.

"We welcome Finland as a new member of the Alliance and fully support Sweden to become a full-fledged member soon. Their accession further strengthens the Alliance and makes the Baltic Sea region as well as the whole Euro–Atlantic area more secure," said the statement.

Hungary was represented in the summit by its ambassador to Latvia.

Stoltenberg will be in Riga due to a scheduled visit to Budapest on Wednesday.

Earlier, Hungarian Prime Minister Viktor Orban told state media that Stoltenberg would visit Budapest "to discuss Hungary's staying out from NATO's Ukraine mission."

The bloc was founded in 2015 in the Romania capital of Bucharest, on the initiative of Romanian President Klaus Iohannis and his Polish counterpart Andrzej Duda during a bilateral meeting following Russia’s annexation of Crimea and subsequent intervention in eastern Ukraine in 2014.

The platform's objective is to align national positions on major issues concerning the security and defense of NATO's eastern flank ahead of alliance summits.

All members of the B9 were either part of the former Soviet Union or members of the defunct Soviet-led Warsaw Pact.