PODGORICA (Reuters) - The Kremlin has a secret list of Montenegrin officials that are banned from entering Russia, due to the small Adriatic republic’s participation in Western sanctions over Ukraine, the country’s Prime Minister Dusko Markovic said on Wednesday.

FILE PHOTO: Montenegro's Prime Minister Dusko Markovic addresses the parliament during a discussion on NATO membership agreement in Cetinje, Montenegro, April 28, 2017 REUTERS/Stevo Vasiljevic

Earlier this week, Montenegro’s foreign ministry summoned the Russian ambassador in Podgorica to protest over the brief detention of a deputy from the ruling Democratic Party of Socialists (DPS) at a Moscow airport.

On Wednesday, Montenegrin pro-government daily Pobjeda quoted sources as saying that the Kremlin has a list of top Montenegrin officials including Markovic that are not allowed to enter Russia.

In a statement Markovic acknowledged he was aware about the existence of such a list, but not who is on it.

“From (Foreign Ministry’s) official record, I saw ... that we were conveyed that a list of persons that are unwanted in Russia remains secret and that we will never know who is on it,” he said.

Kremlin officials declined to comment on Markovic’s remarks.

In 2014, Montenegro imposed sanctions against Russia, embracing European Union policies over Russia’s annexation of Crimea in Ukraine that includes a entry ban for some officials. Moscow initially retaliated by banning food imports from Montenegro.

The travel ban would aggravate relations between Podgorica and the Kremlin, which opposed Montenegro’s NATO membership bid. The ex-Yugoslav republic will join the Alliance next month.

On Monday, Russian Foreign Ministry spokeswoman Maria Zakharova said that the Kremlin reserves the right to retaliate against Montenegrin sanctions.

Ties between Montenegro, a EU hopeful, and Russia, previously its key Slavic and Orthodox Christian ally and a top investor, worsened after the country sought to join NATO.

Last October Montenegro said Russian spy agencies and local pro-Russian parties conspired to halt country’s NATO bid, assassinate the-then Prime Minister Milo Djukanovic and bring opposition to power. The Kremlin dismissed that as absurd.