MOSCOW, Nov 27 (AFP) - Kremlin spokesman Dmitry Peskov on Sunday said attempts to break up a Russian-led security alliance had always existed and would continue to do so, but insisted that the alliance remained in high demand following criticism this week from Armenia.

Armenian Prime Minister Nikol Pashinyan called into question the effectiveness of the six-nation Collective Security Treaty Organisation (CSTO) at a summit this week.

Armenia requested assistance from the organisation in September, but received only a promise to send observers. Pashinyan contrasted that with the alliance's rapid decision in January to send troops to CSTO member Kazakhstan to help President Kassym-Jomart Tokayev survive a wave of unrest.

"There have always been attempts to (bring about) the CSTO's disintegration," news agencies quoted Peskov as saying in an interview broadcast on state television.

"But at least now we see that, despite all the difficulties, despite the possible contradictions even between member countries, this structure remains in high demand," he said. "And it fully demonstrated its relevance and effectiveness, meaning the resolution of the situation in Kazakhstan."

Kazakhstan's Tokayev, who has openly defied major ally Russia over its actions in Ukraine, won re-election this month and is set to meet with Russian President Vladimir Putin in the Russian city of Orenburg on Monday.

Russia, the dominant player in the CSTO, risks losing influence in parts of the former Soviet Union that it has long seen as its sphere of influence, as the conflict in Ukraine drags into its 10th month.