NATO head Jens Stoltenberg told AFP Thursday there was still a "strong" Russian presence in eastern Ukraine in support of pro-Moscow rebels although a recent ceasefire seems to be holding.

"There is no doubt that there is a strong Russian presence in the eastern part of Ukraine," Stoltenberg said in an interview at NATO HQ in Brussels. "There (are) Russian forces there, there (is) Russian equipment and Russia continues to train and to assist the separatists."