MOSCOW, Feb 27 - A former senior aide to Russian President Vladimir Putin has warned that Ukraine will never be able to regain control over the separatist-controlled east, AP reported Wednesday.

Vladislav Surkov, who lost his job as Putin's adviser on Ukraine earlier this month, said in remarks published Wednesday that he stepped down because of a shift in the Kremlin course on the Ukrainian conflict. He didn't spell out specific reasons for his departure, saying only that it was due to a “change in context” on Ukraine.

President Volodymyr Zelenskiy has made settling the conflict in eastern Ukraine his top priority. December's summit of Russia, Ukraine, France and Germany failed to achieve a breakthrough, but the four leaders made a deal on a prisoner exchange and agreed on further moves toward settling the conflict in the east.

Surkov hailed leaders of separatists in eastern Ukraine as “true warriors” and “real heroes.” He charged that Ukraine will never be able to restore its control over the rebel-controlled territories.

Surkov's harsh statement contrasted sharply with the usual rhetoric from the Kremlin, which has urged Ukrainian authorities to engage in dialogue with the rebels and work out a political settlement that would offer broad autonomy to the rebel regions in line with the 2015 peace deal. Such autonomous status was seen by the Kremlin as a key lever to hold off Ukraine's aspiration to join NATO.

Observers in Moscow attributed Surkov's dismissal to the Kremlin's intention to take a less hawkish line on Ukraine, taking advantage of Zelenskiy's intention to move toward a settlement. Surkov was succeeded as the Kremlin's point man on Ukraine by another longtime Putin aide, Dmitry Kozak.

Asked Wednesday if the Russian policy on Ukraine has shifted, Putin spokesman Dmitry Peskov shrugged off Surkov's claim, saying that the Kremlin adheres to a 2015 peace agreement brokered by France and Germany as the basis for political settlement.

The conflict in Ukraine's mostly Russian-speaking industrial east erupted in April 2014 — weeks after Russia's annexation of the Crimean Peninsula. More than 14,000 have been killed in fighting between Ukrainian forces and Russia-backed separatists. (ap/ez)