The convoy of more than 200 trucks bringing aid to war-torn Eastern Ukraine returned to Russia after a brief excursion into Ukrainian territory. Russia's neighbor accused Russia of violating its territory by entering Ukraine without Kiev's consent.

Both the United States and Ukraine have condemned Russia's unilateral action, saying it violates Ukraine's sovereignty. The Pentagon's spokesman, Rear Admiral John Kirby, told reporters that the U.S. would not condone Russia's actions, according to Department of Defense News.

"We strongly condemn this action and any actions that Russian forces take that increase tensions in the region," Kirby said. "Russia should not send vehicles, persons or cargo of any kind into Ukraine, whether under the guise of humanitarian convoys or any other pretext, without Kyiv's express permission."

Kirby then demanded Russia remove its troops and vehicles from Ukraine's territory, adding that "failure to do so will result in additional costs and isolation."

Expressing his concern was also the United Nations Secretary-General Ban Ki-moon who released a statement via a spokesman on the incident.

"The Secretary-General follows with deep concern reports that a Russian aid convoy has crossed the border into Ukraine without the permission of the Ukrainian authorities. While recognising the deteriorating humanitarian situation, any unilateral action has the potential of exacerbating an already dangerous situation in eastern Ukraine," the statement said.

The Secretary-General expressed his hope for a peaceful resolution and for humanitarian aid to reach the area of fighting. According to the Washington Post, Ukrainians in rebel-held territory also hope for the arrival of aid as supplies in rebel-controlled city of Luhansk continue to dwindle. The city has been deprived of electricity for about three weeks, and hospitals are running on the last drops of fuel for their generators. There is also a water shortage, as most utilities in the city have ceased to work.

However, Ukraine accused Russia of violating its territory and demanded Russia leave, according to the Wall Street Journal. Russian media reported that some trucks from the large convoy had arrived in the city though Ukraine claims to have the city surrounded.

The Observer reports the Organization for Security and Cooperation in Europe (OSCE) confirmed the crossing of 227 Russian trucks and said that Red Cross personnel supervised the distribution of supplies.

However, The New York Times reports that Russia has recalled its convoy under international pressure. Germany has pledged more than $600 million to rebuild the war-torn areas.