In a sign of growing rifts between member states of the Russian-led Eurasian Economic Union (EEU) free trade bloc, Prime Minister Karim Massimov of Kazakhstan, the bloc’s current chair, has suggested rescheduling a meeting on April 8 from the Armenian capital of Yerevan to Moscow.

Massimov did not explain the move but the Armenian prime minister’s press office linked it to the recent escalation of fighting over the disputed region of Nagorno-Karabakh between Armenia and Azerbaijan, Kazakhstan’s “strategic” partner in the Caucasus.

According to Russia’s RBK, citing sources in the Russian government, the meeting of the Eurasian Intergovernmental Council would have been seen as support to one of the conflicting parties, namely Armenia, and will therefore be cancelled. Armenia is a member of the EEU, along with Belarus, Kazakhstan, Kyrgyzstan and Russia.

A spokeswoman for Russian Prime Minister Dmitry Medvedev told RBK that Russia was waiting for an official decision from Kazakhstan, which is currently chairing the EEU, to cancel the meeting in Yerevan on April 8 and move it Moscow on a later date.

“No final decision has yet been taken in this regard,” the Kazakh governmental press service told Tengrinews on April 7, confirming that Massimov would not be going to Yerevan. “It is not clear yet as why he would not go [to Yerevan], but it was decided that he would not go.”

On April 6 Massimov called his Armenian colleague Hovik Abrahamyan to suggest the meeting be moved to Moscow, Armenia’s Hayastannews.com website reported, citing the Armenian prime minister’s press office. Abrahamyan told the Kazakh prime minister that “there are no serious grounds” for relocating the meeting, Hayastannews.com said. The Armenian premier has not yet decided whether he would attend the meeting if it were moved to Moscow, the news agency added.

Massimov’s decision not to go to Yerevan shows that Kazakhstan is still unhappy about the Kremlin’s decision to bring Armenia into the EEU and is showing open support to its close diplomatic and commercial partner Azerbaijan.

In May 2014 during the signing of a treaty on the establishment of the EEU, President Nursultan Nazarbayev prevented Yerevan from signing the treaty as a founding member, citing border disputes between Armenia and Azerbaijan over Nagorno-Karabakh. Armenia still joined the bloc in January 2015.

In a further blow to Armenia, this March Nazarbayev told the newly-appointed Azerbaijani ambassador to Kazakhstan, Rashad Mammadov, that Baku was Astana’s “strategic” partner in the Caucasus.

Kazakhstan and Azerbaijan share a similar cultural and linguistic heritage as Turkic nations. Following Russian bans on transit of Western, Ukrainian and Turkish goods through its territory, Kazakhstan and Azerbaijan have realised their potential as transit hubs sending cargo across the Caspian Sea.

Bilateral trade between the two countries, despite falling from $490mn in 2008 – before Kazakhstan set up a customs union with Russia and Belarus in 2010 – to $90mn in 2015, still dwarfs Kazakhstan’s trade with Armenia, which stood at $4.6mn in 2015.

All EEU member states together with Tajikistan are also members of the Russia-led Collective Security Treaty Organisation (CSTO) but the political and military bloc has been unwilling to intervene in conflicts involving its member states.

“The positions of member states of the CSTO on this issue have been expressed many times – it is the suspension of hostilities and peaceful solution to the Nagorno-Karabakh conflict,” Nikolai Bordyuzha, the bloc’s secretary general, said following the outbreak of the conflict on April 2.