The leaders of the United States, Britain, France, Germany, and Italy agreed by telephone on July 28 that they would impose new sanctions on Russia for its role in the crisis in Ukraine.
The French president's office released a statement about the call that said the five leaders "confirmed…their intention to adopt new measures against Russia."
The statement added that the leaders said they would watch carefully to see if Russia was giving direct military support to the separatists.
The call came as the United States and the European Union weigh up tougher sanctions against Russia amid the crisis over Malaysia Airlines Flight MH17, which went down over eastern Ukraine on July 17.
The West accuses separatists in eastern Ukraine of shooting down the passenger jet and blames Russia for supplying the rebels with equipment capable of doing so.
After the phone call, White House deputy security adviser Tony Blinken said the European leaders made clear in the conversation that they were prepared to impose new sanctions on Russia's financial, energy, and arms sectors.
Blinken said the United States would be announcing new sanctions against Russia soon.
Blinken spoke about the downed Malaysian airliner saying that, while it is still not clear "exactly who pulled the trigger," Moscow remains culpable since the weapon system used to shoot down the plane came from Russia.
He also said that there are likely still SA-11 missile launchers in Ukraine similar to the one that brought down the Malaysian plane and some of them might be in the hands of pro-Russian separatists.
Efforts to investigate the site of the plane crash have been hampered in recent days by heavy fighting around the area.
On July 28, Russia's ambassador to the UN and a separatist military commander said Ukrainian government forces were moving to seize control of the region where the plane's wreckage is located.
Igor Strelkov, the defense minister of the self-declared Donetsk People's Republic, claimed his forces repelled the worst attacks and destroyed several armored vehicles in fighting near the town of Shakhtarsk.
Russia's UN Ambassador Viltay Churkin said the attempt by Ukrainian government forces to take control of the crash site violated a UN resolution.
Ukrainian news agency UNIAN reported separatists were using Grad multiple rocket launchers to shell civilian areas of Shakhtarsk.
Government troops have also reportedly "entered" the towns of Shakhtarsk and Torez. National Guard units are also reported to be on the outskirts of the city of Horlivka.
The Ukrainian government said on July 28 that its forces had captured the city of Debaltsevo and the hill of Saur-Mohyla, in the Donetsk region.
Ukrainian Foreign Minister Pavlo Klimkin was in Washington on the same day and he said separatists were ignoring calls for a cease-fire in the crash area so that they could destroy evidence of their involvement in shooting down the plane.
With reporting by Reuters, AFP, AP, UNIAN, ITAR-TASS, and Interfax