Moldova said on Thursday it would bar its officials from visiting Russia because they were being subjected to "humiliating" abuse and harassment by some members of Moscow's security apparatus.

The government of the small ex-Soviet republic said in a statement it believed the abuse was revenge for an investigation of what it said was a $22 billion scheme to launder Russian money through Moldova's financial system.

The spat has erupted at a delicate time, as Moldova's newly-elected president is looking to pull his country closer to Moscow while its staunchly pro-Western government seeks closer ties with and eventual membership of the European Union.

A reaction to treatment from Russia

Moldovan lawmakers, government officials and intelligence services "are being abusively stopped on entry to the Russian Federation, interrogated and treated in a humiliating manner by representatives of a Russian special/intelligence service," the government statement said.

Russia's security services and foreign ministry did not immediately respond to a request for comment on Moldova's accusations.

“Until a solution is found to this issue, Moldovan officials are asked to abstain from visits to the Russian Federation,” the Moldovan statement said.

Authorities in Chisinau say Russian money has been laundered through a Moldovan bank with the collusion of Moldovan judges and some central bank officials. Fourteen judges and a prominent Moldovan businessman have been arrested.

President denounces move

Moldova, Europe's poorest country, borders EU member Romania, with which it has close linguistic and cultural ties, but remains heavily reliant on Russian energy supplies.

Relations with Moscow soured after Moldova signed a political and trade pact with the EU in 2014, prompting Russia to slap a retaliatory ban on Moldovan produce.

President Igor Dodon, who travels to Russia next week, denounced the move on Thursday to stop Moldovan officials from traveling as “abnormal” and said it would hurt efforts to build better relations with Moscow.

Requests ignored

In its statement, the government said one Moldovan interior ministry official had been stopped 35 times while entering and exiting Russian territory at a Moscow airport.

It also accused Russian security officials of spreading false information about high-ranking Moldovans as a ruse to get them put onto international watch lists.

The Moldovan government said the Russian authorities had refused to co-operate with its money-laundering investigation and had ignored official requests for help.