Kiev/Berlin, Shawwal 27, 1435, Aug 23, 2014, SPA -- German Chancellor Angela Merkel travelled to the Ukrainian capital Kiev on Saturday for talks on the escalating conflict with Russia over the pro-Russian separatist rebellion, according to dpa. Merkel's visit comes a day after Russia sent an aid convoy consisting of some 280 trucks into the conflict zone in eastern Ukraine, prompting Ukrainian accusations of a direct invasion. Latest reports from the area on Saturday said some of the Russian trucks which had crossed over the border had delivered goods in the rebel stronghold of Luhansk, and returned to Russian territory. During her visit, Merkel is expected to ask Ukrainian President Petro Poroshenko to temper the military operation against the separatists. Merkel is also planning to meet Ukrainian Prime Minister Arseniy Yatsenyuk and mayors from across the country, including the Donetsk region that is a focus of the insurgency. Poroshenko plans to meet on Tuesday with his Russian counterpart Vladimir Putin. On Friday, Merkel said Russia risked escalating an already tense situation. She raised the issue during phone calls with Putin, Poroshenko and Barack Obama of the United States. Despite Russia's actions, Merkel said the aid convoy should be allowed to reach those in need in rebel-held areas, and that Ukrainian aid convoys should be allowed to reach the same areas. Putin rejected the criticism from Merkel. "The trip to Kiev is difficult and is an expression of support," said Merkel's spokesman, Steffen Seibert. "Our aim is for both sides to agree to a ceasefire." NATO Secretary General Anders Fogh Rasmussen said Russia's decision on the convoy was "a further violation of Ukraine's sovereignty by Russia." The US has demanded that Russia remove the vehicles immediately, and a spokesman for EU foreign policy chief Catherine Ashton said the Russian convoy was a "clear violation" of Ukraine's borders. UN Secretary General Ban Ki-moon expressed "deep concern." Russia's UN ambassador Vitaly Churkin insisted the trucks carried humanitarian aid such as food, medical supplies, electric generators and sleeping bags. Ukraine says it fears that the convoy might be used to supply pro-Russian insurgents, and had demanded detailed cargo lists. In another development, there's been condemnation of the killing on Friday of Lithuania's honorary consul in the rebel-held Ukrainian city of Luhansk. Lithuania, which has been strongly critical of Russia over the Ukraine crisis, blamed "terrorists" for the killing of the official. --SPA 12:08 LOCAL TIME 09:08 GMT www.spa.gov.sa/w