Russian advance in Ukraine stopped on all fronts - official

Russia's advance in Ukraine has been 'stopped on all fronts,' Ukrainian presidential adviser Alexey Arestovych said on Sunday.

Ukrainian forces are putting up a stronger fight as clashes continue on the ground, Arestovych said in a video message on social media.

He asserted that the Russian forces have "no power" to change the situation.

Russian soldiers and officers are feeling the pressure as commanders are being accused of "cowardice and weakness of character" after inspections by Russia's Federal Security Service, Arestovych claimed.

Earlier on Sunday, the Ukrainian military said it had inflicted more losses on Russian forces in ongoing clashes, with approximately 14,700 Russian soldiers killed in Ukraine so far.

Ukrainian forces have destroyed a total of 96 Russian aircraft, 118 helicopters, 476 tanks, 1,487 armored carriers, 947 vehicles, 21 UAVs, 60 fuel tankers and three boats, according to the latest update from the Ukrainian General Staff.

At least 230 Russian artillery systems, 74 multiple rocket launcher systems and 44 air defense systems have also been destroyed, it added.

Claims on casualties and damages from both sides, however, have not been independently verified.

According to UN estimates, at least 902 civilians have been killed and around 1,460 injured in Ukraine since Russia launched war on its western neighbor on Feb. 24.

The UN has said the real figures are likely to be much higher as conditions on the ground make verification difficult.

The hostilities have also driven 10 million people from their homes, according to the UN refugee agency.

UN data shows almost 3.4 million refugees have fled from Ukraine since the war began, with more than 2 million taken in by neighboring Poland, close to 530,000 by Romania and over 362,000 by Moldova.

Some 6.5 million people are estimated to be internally displaced in the country.