Ukraine's President Petro Poroshenko made a call for peace following one-on-one talks with Russia's President Vladimir Putin over the conflict wracking eastern Ukraine.
"Our main goal is peace. We demand resolute actions that will bring peace to the Ukrainian land," he said on Wednesday in a statement posted on his official website.
It's not yet clear how the apparent diplomatic progress will translate into a halt in fighting on the ground.
Ukraine's National Defense and Security Council told reporters at a briefing Wednesday that Russian forces were directing massive artillery fire over the border at the town of Novoazovsk, in the south of the Donetsk region.
Russian forces and pro-Russia rebels have seized villages around the town, the NSDC said.
The NDSC also claimed that members of a Russian tactical battalion were present in the village of Pobeda, in Ukraine's Luhansk region.
"If these troops got lost and accidentally found themselves in Ukraine as well, they should go back East," the update said.
On Tuesday, Ukraine's Security Service said it had detained 10 Russian soldiers in Ukraine. Russian state media cited a source in the Russian Defense Ministry as saying the soldiers had been patrolling the border and "most likely crossed by accident" at an unmarked point.
Moscow has repeatedly denied allegations by Kiev that it has sent troops over the border.
Poroshenko and German Changellor Angela Merkel discussed the outcome of the Minsk meeting by phone Wednesday, his office said.
Putin: 'Positive' meeting
Poroshenko said Tuesday's talks in Minsk, Belarus, with Putin focused on the issue of border control "to prevent the movement of armored vehicles, mercenaries and ammunition."
Ukraine and Russia have agreed to begin consultations between border guards and general staff commanders, he added via Twitter.
The meeting, which lasted nearly two hours, was the first for the leaders since they met briefly in June on the sidelines of events to commemorate D-Day.
It came at a summit held by the Moscow-led Customs Union, a trade bloc which also includes Belarus and Kazakhstan. Senior European Union officials were also present in Minsk, with EU foreign policy chief Catherine Ashton at their head.
Putin said the bilateral meeting was "positive" and that he and Poroshenko agreed on the need to "renew our dialogue."
Putin told reporters that Russia couldn't be involved in ceasefire talks because those discussions should be between Kiev and separatists in eastern Ukraine. Moscow is willing to assist, he added.
Russian Foreign Minister Sergey Lavrov, in remarks Wednesday broadcast by state-run TV channel Russia 24, said it was important that Ukraine engaged in dialogue with all parts of the country.
He also indicated that Russia would send another aid convoy into eastern Ukraine. More than 200 trucks crossed the border from Russia last week without Ukraine's permission, a move condemned by the West as a violation of Ukraine's sovereignty.
Ukraine and the West have repeatedly accused Moscow of fomenting the unrest by supporting and arming the pro-Russia rebels in eastern Ukraine's Luhansk and Donetsk regions.
Moscow in turn says Kiev has precipitated a humanitarian crisis in the predominantly Russian-speaking east of the country by pursuing its military campaign against the rebels.
'Road map' for peace
Speaking after the talks, at a joint news conference with Ashton, Poroshenko said a "road map" would be drawn up on the basis of his previously announced peace plan.
Consultations will be made through a contact group to try to reach a ceasefire as soon as possible, he said.
That ceasefire would be monitored by the Organization for Security and Cooperation in Europe, he said, "which will be able to monitor and verify the ceasefire, which has to be two-sided by any means."