U.S. President Joe Biden said Sunday that the G-7 leading economies will ban imports of gold from Russia, the latest in a series of sanctions that the club of democracies hopes will further isolate Russia economically over its invasion of Ukraine.

A formal announcement was expected Tuesday as the leaders meet for their annual summit.

Biden and his counterparts will huddle on the summit's opening day Sunday to discuss how to secure energy supplies and tackle inflation, aiming to keep the fallout from Russia’s invasion of Ukraine from splintering the global coalition working to punish Moscow.

Hours before the summit was set to open, Russia launched missile strikes against the Ukrainian capital Sunday, striking at least two residential buildings, Kyiv Mayor Vitali Klitschko said. They were the first such strikes by Russia in three weeks.

Senior Biden administration officials said gold is Moscow's second largest export after energy and that banning imports would make it more difficult for Russia to participate in global markets.

British Prime Minister Boris Johnson said a ban by G-7 countries on Russian gold will "directly hit Russian oligarchs and strike at the heart of Putin’s war machine."

"Putin is squandering his dwindling resources on this pointless and barbaric war. He is bankrolling his ego at the expense of both the Ukrainian and Russian people," Johnson said. "We need to starve the Putin regime of its funding."

Britain says the value of gold exports to the Russian elite has increased since the war began as wealthy Russians seek to skirt Western sanctions.

In recent years, gold has been the top Russian export after energy – reaching almost $19 billion or about 5% of global gold exports, in 2020, according to the White House.

Of Russian gold exports, 90% was consigned to G-7 countries. Of these Russian exports, over 90%, or nearly $17 billion, was exported to the U.K. The United States imported less than $200 million in gold from Russia in 2019, and under $1 million in 2020 and 2021.

The G-7 was expected to formally announce the ban on Russian gold on Tuesday, according to Biden administration officials, who spoke on condition of anonymity to discuss details before the announcement.

Biden arrived in Germany’s picturesque Bavarian alps early Sunday morning to join his counterparts for the annual meeting of the world's leading democratic economies, where the reverberations from the brutal war in Ukraine will be front and center in the discussion. He and the allies aim to present a united front in support of Ukraine as the conflict enters its fourth month.

Biden attended Mass performed by a U.S. Army priest, the White House said. The president was opening the visit by meeting with the summit’s host, German Chancellor Olaf Scholz, before spending the afternoon in both formal and informal settings with the leaders of Britain, Canada, France, Germany, Italy, Japan and the European Union.

John Kirby, spokesperson for the White House National Security Council, said Saturday that the summit will address problems such as inflation and other "challenges in the global economy as a result of Mr. Putin’s war – but also how to continue to hold Mr. Putin accountable" and subject to "constant consequences."

"There will be some muscle movements," Kirby said from Air Force One as Biden flew to Germany.

Among the issues to be discussed are price caps on energy which are meant to limit Russian oil and gas profits that Moscow can put to use in its war effort. The idea has been championed by U.S. Treasury Secretary Janet Yellen.

A senior German official, speaking on condition of anonymity consistent with department rules, said the U.S. idea of price caps was being discussed intensely, in terms of how it would work exactly and how it would fit with the U.S., EU, British, Canadian and Japanese sanctions regimes.

Officials were also set to discuss how to maintain commitments to addressing climate change while also solving critical energy supply needs as a result of the war.

"There’s no watering down of climate commitments," Kirby said.

Biden is also set on Sunday to formally launch a global infrastructure partnership meant to counter China’s influence in the developing world, which he had named "Build Back Better World" and introduced at last year’s G-7 summit.

Kirby said Biden and other leaders would announce the first projects to benefit from what the U.S. sees as an "alternative to infrastructure models that sell debt traps to low- and middle-income partner countries, and advance U.S. economic competitiveness and our national security."

After Germany wraps up on Tuesday, Biden will travel to Madrid to meet with the leaders of the 30 members of NATO to align strategy on the war in Ukraine.