Vienna will expel a Russian diplomat, Austria's foreign ministry said Monday, as media reported he had been involved in economic espionage for years.

"We can confirm that a Russian diplomat will be expelled," the ministry said in a statement to AFP, adding his behaviour had violated diplomatic relations.

The statement gave no further details. Media reports said the diplomat had been given until September 1 to leave the country.

The Kronen Zeitung tabloid said he had spied with the help of an Austrian citizen at a high-tech enterprise for years.

The Russian Embassy in Vienna slammed the expulsion order. "We are outraged by the authorities' unfounded decision, which is detrimental to constructive relations. We are sure that a corresponding response from Moscow will not be long in coming," it said in a tweet.

Austria has boasted close ties with Russia in recent years.

In 2018, Austria said it would not follow a number of other EU countries in expelling Russian diplomats over the poisoning of a former Russian spy in Britain, stressing its neutrality.