Russian President Vladimir Putin took another swipe at Turkey during his State of the Nation address Thursday. After saying Turkish leaders “will regret” shooting down a Russian fighter jet last week, Putin said, “Allah decided to punish Turkey leaders by making them lose their minds,” the state-owned Sputnik news agency reported.

Relations between Russia and Turkey have been tense for some time, but the situation was exacerbated last week when Turkey shot down a Russian military jet near the Syrian border, saying it had violated its airspace. The Russian pilot who survived the incident denied the plane was over Turkey, and Putin called the incident a “stab in the back.”

Earlier this week, Putin accused Turkey of shooting down the Russian Su-24 bomber on Nov. 24 to protect a secret oil trade with the Islamic State terrorist group -- a charge that Turkish leaders have denied. He had previously called Turkish officials “accomplices of terrorists,” and the country is known for being a thoroughfare for fighters entering Syria to join the Islamic State.

Russian Deputy Defense Minister Anatoly Antonov charged Wednesday that Turkish President Recep Tayyip Erdoğan and his family had personal ties to the ISIS oil trade.

“President Erdoğan and his family are involved in this criminal business,” Antonov said in Moscow, the Associated Press reported. “We know the price of Erdoğan’s words … Turkish leaders won’t step down and they won’t acknowledge anything even if their faces are smeared with the stolen oil.”

Antonov and other Russian officials claimed that ISIS militants make $2 billion per year from the illegal oil trade, and said Russia’s airstrikes have cut the terror group’s profits in half. Moscow has been conducting airstrikes in Syria at the request of its ally Syrian President Bashar Assad, whom Turkey opposes, since Sept. 30.

Putin’s address to the Russian parliament Thursday focused on the country’s interactions with Turkey and recent terrorism around the world.

​"It's the duty of every civilized country to take part in the defeat of terrorists," the president said, Sputnik reported.

He also said his country would have liked to cooperate with Turkey on fighting terrorism before last week’s plane incident. "I do not understand why they did it. Any problem — even that which we might have missed — could have been dealt with in a different way," Putin added.