Leaders of the Group of Seven industrialized nations on Thursday vowed to keep close watch on any attempt to help Russia evade sanctions imposed over its invasion of Ukraine, in a possible warning to countries such as China that may seek to align with Moscow.

The announcement came as leaders from the United States, Japan and Europe gathered in Brussels for a series of summit meetings to affirm their resolve to stand with Ukraine and further pressure Russia to cease the military campaign it started a month ago.

"We underline our resolve to impose severe consequences on Russia, including by fully implementing the economic and financial measures we already imposed," the G-7 leaders said in a statement as they met in person for the first time since the invasion began.

"We stand ready to apply additional measures as required," they added.

Japanese Prime Minister Fumio Kishida (3rd from L), U.S. President Joe Biden (5th from L) and other leaders of the Group of Seven nations pose for a group photo alongside representatives of the North Atlantic Treaty Organization and the European Union on March 24, 2022, in Brussels. (Kyodo)

Under a newly launched initiative, Britain, Canada, Germany, France, Italy, Japan and the United States plus the European Union plan to monitor the full implementation of sanctions and coordinate their responses to evasive measures.

Russia's aggression has been met with actions aimed at isolating the country from the global economy, including freezing the Russian central bank's assets, banning key Russian financial institutions from a major international payment system and imposing export bans and controls to cut Russia off from advanced technologies.

A senior U.S. official said the Russian central bank may be trying to use its gold reserves to prop up the falling ruble and that the G-7 will make clear that any transaction involving gold related to the central bank is prohibited.

In coordination with other G-7 members, the United States announced new sanctions targeting over 400 Russian elites, members of parliament and defense companies. It also vowed to provide more than $1 billion in humanitarian assistance to support people in Ukraine and others suffering from food insecurity and other impacts of the war.

Japanese Prime Minister Fumio Kishida attended the G-7 meeting as the sole Asian member in the group, with the Ukraine crisis seen as having implications for the Indo-Pacific, a region facing increasing Chinese military assertiveness.

Kishida said Japan will provide $100 million in fresh humanitarian aid to support Ukraine and nearby countries affected by the crisis, in addition to the $100 million in support already pledged. He also said more Russian individuals and entities will be added to the sanctions list.

Japanese Prime Minister Fumio Kishida (R) arrives at the headquarters of the North Atlantic Treaty Organization in Brussels on March 24, 2022. (Kyodo) ==Kyodo

As the conflict has pushed global energy prices and food costs higher amid concerns over supply disruptions, the G-7 members agreed to work with oil and gas producing countries to ensure stable and sustainable global energy supplies and to take actions to address the evolving global food security crisis.

Earlier in the day, NATO leaders agreed to provide additional security support so that Kyiv can defend itself, including equipment to help protect against chemical, biological and nuclear threats.

In an effort to bolster its defense in the eastern part of the 30-member alliance that is closer to Russia, four additional multinational battlegroups will be established in Bulgaria, Hungary, Romania and Slovakia, in addition to the four already in the Baltic countries and Poland.

In a statement issued after the summit, the North Atlantic Treaty Organization called on China to "abstain from supporting Russia's war effort in any way, and to refrain from any action that helps Russia circumvent sanctions."

The U.S. government has recently expressed its concern that Beijing is considering directly assisting Moscow with military equipment to use against Ukraine.

While Ukraine forces have mounted stiffer-than-expected resistance since the invasion started on Feb. 24, Russia has continued its attack, and the brutality has increased as its targets have included hospitals, schools and places of shelter. Millions have fled their homes, pouring into neighboring countries.

Amid concerns that Russia may use chemical, biological or nuclear weapons in Ukraine, NATO and the G-7 both warned against such tactics.

Asked whether the United States would take military action if Russia were to use chemical weapons, President Joe Biden said at a press conference, "We would respond." But he added that the "nature of the response would depend on the nature of the use."

In an effort to further isolate Russia, the G-7 leaders agreed that international organizations and multilateral fora should no longer conduct their activities with Russia "in a business as usual manner."

Biden said he believes Moscow should be removed from the Group of 20. The G-20 groups emerging economies including China plus the G-7.

As Japan has been acting on par with its other G-7 peers in imposing tough sanctions against Moscow, Russia has announced the suspension of negotiations for a bilateral postwar peace treaty, dampening prospects of any progress in a decades-long territorial row Tokyo has hoped to resolve.

During the G-7 meeting, Kishida said that Russia's latest move will not stop Tokyo from "decisively responding" to the aggression.

He also told reporters that the G-7 members affirmed their intention to work together in dealing with North Korea's nuclear and missile threats in the wake of Thursday's launch of an intercontinental ballistic missile, the first such test since 2017.

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