Standing on broken glass in her wrecked living room, Valentina Balabai thanked her love of animals for keeping her and her husband alive that morning.

"When the shells hit he was out walking my dog and I was feeding some stray cats -- otherwise we'd both be corpses," the blonde pensioner told Agence France Presse.

Ukraine's new leader congratulated his troops on Tuesday with the "first victory" in their resumed campaign against separatist insurgents, announcing they had regained control of one Russian border crossing.

President Petro Poroshenko's office said government forces had seized back the Dovzgansky crossing in Lugansk -- one of 24 in the separatist province, most of which are under rebel control.

President Vladimir Putin on Tuesday described the conflict in Ukraine as the culmination of Western efforts to contain Russia and sought to play Moscow's "natural partner" Europe against the United States.

In a keynote speech laying out his foreign policy priorities, Putin lambasted the U.S. drive to sideline Moscow and said Europe has become a victim of "short-sighted, ideology-driven approaches."

The European Union is preparing new sanctions against Russia over the conflict in Ukraine but no decision has been taken yet, EU diplomats told AFP on Tuesday.

Ambassadors from the 28-nation bloc met in Brussels and decided that "the preparation of sanctions will be intensified" ahead of an extraordinary meeting next Monday, said a diplomat who asked not to be named.

Two journalists from Russian television channel Ren TV were hurt by mortar fire in eastern Ukraine on Tuesday, a day after one of their colleagues was shot and killed there.

Reporter Denis Kulaga and cameraman Vadim Yudin were hurt when a "mortar shell exploded next to them" in the Lugansk area not far from the Russian border, the liberal station announced on Twitter.

France said Tuesday there would be no let-up in diplomatic efforts to bring peace to Ukraine as the Kiev government announced the end of a ceasefire in the restive east of the country.

France and Germany led efforts overnight to "de-escalate" the conflict with talks held between the foreign ministers of both countries and their counterparts in Russia and Ukraine, French Foreign Minister Laurent Fabius said.

Ukrainian tanks and fighter bombers launched a ferocious assault against pro-Russian separatist insurgents on Tuesday after Kiev dismissed European pressure to save a tenuous 10-day truce.

The resumption of the worst fighting in Europe in nearly two decades drew the instant wrath of Russian President Vladimir Putin and set off a new international scramble to regain some control over events in the strategic ex-Soviet state.

Russian President Vladimir Putin on Monday called for Ukraine's truce to be extended and for new talks between Kiev and separatists, just hours before the current ceasefire expires.

"Vladimir Putin stressed the importance of extending a ceasefire as well as creating a reliable mechanism to control the observance of the truce with an active role of the OSCE," the Kremlin said in a statement after Putin held talks with his French counterpart Francois Hollande, Germany's Angela Merkel and Ukrainian President Petro Poroshenko.

France and Germany on Monday looked set to ramp up pressure on Russia to stem the Ukraine conflict in frantic negotiations as the clock ticks down on a shaky truce.

French President Francois Hollande and German Chancellor Angela Merkel were due to hold four-way telephone talks with Kremlin strongman Vladimir Putin and new Kiev leader Petro Poroshenko ahead of a 1900 GMT deadline for an unsteady ceasefire to end in violence-hit eastern Ukraine.

French President Francois Hollande and German Chancellor Angela Merkel spoke for "over two hours" with their Russian and Ukrainian counterparts Sunday, the Elysee said, with the latest ceasefire deadline in Ukraine looming.

During the telephone exchange with Russia's Vladimir Putin and Ukraine's leader Petro Poroshenko, the leaders discussed "the importance of making new concrete advances in the security situation on the ground, prolonging the ceasefire and putting in place the peace plan" presented by Ukraine, the French president said in a statement.