Turkey is free to purchase weapons from any country, whether it is NATO member or not, President Recep Tayyip Erdogan said.

He emphasized that Turkey could “even jointly produce weaponry” with any country including Russia and China, and is preparing itself accordingly, Daily Sabah reported.

“It is not appropriate to try to block a country if there is free market economy involved,” Erdogan said.

In December Turkey signed a $2.5 billion agreement with Russia to purchase S-400 missile system, the move that caused U.S. discontent.