President Barack Obama and the Group of Seven nations warned Russia on Monday it faced damaging economic sanctions if President Vladimir Putin takes further action to destabilize Ukraine following the seizure of Crimea, the Wall Street Journal reported.

Leaders of the Group of Seven nations, meeting without Russia, agreed to hold their own summit this year instead of attending a planned G8 meeting in the Russian Olympic venue of Sochi, along the Black Sea coast from Crimea, and to suspend their participation in the G8 until Russia changes course, according to the WSJ.

Kiev ordered its remaining troops to withdraw from Crimea and Russian forces captured a Ukrainian marine base and a landing ship in the region while leaders of the United States, Germany, France, Britain, Italy, Japan and Canada condemned what they called "Russia's illegal attempt to annex Crimea in contravention of international law," the WSJ reported.

They also agreed their energy ministers would work together to reduce dependence on Russian oil and gas and increase energy security, according to the WSJ.

"We remain ready to intensify actions including coordinated sectoral sanctions that will have an increasingly significant impact on the Russian economy, if Russia continues to escalate this situation," the G7 said in a joint statement, the WSJ reported.

The G7 leaders, who met on the sidelines of a nuclear security summit in The Hague, said they would convene again in Brussels in early June, the first time since Russia joined the G8 in 1998 that it will have been shut out of the annual summit of industrialized democracies, according to the WSJ.

They also urged the International Monetary Fund to reach a rapid agreement with Ukraine to unlock urgently needed financial aid for the country's shattered economy, the WSJ reported.

Obama, who has imposed tougher sanctions on Moscow than European leaders over its takeover of the strategic Crimean peninsula, told reporters: "Europe and America are united in our support of the Ukrainian government and the Ukrainian people," according to the WSJ.

"We're united in imposing a cost on Russia for its actions so far," President Obama said of the visa bans and asset freezes slapped on senior Russian and Crimean officials, the WSJ reported.