NATO Secretary-General Jens Stoltenberg said on Friday Ukraine’s counter-attack against Russian troops had been very effective but warned nations should prepare for the long haul as this did not signal the beginning of the end of the war.

“It is of course extremely encouraging to see that Ukrainian armed forces have been able to take back territory and also strike behind Russian lines”, - Stoltenberg told BBC radio.

“At the same time, we need to understand that this is not the beginning of the end of the war, we need to be prepared for the long haul”.