A U.S. plane was forced to change its course while in Syria to avoid close contact with a Russian aircraft, which might have been conducting airstrikes, the Pentagon said Wednesday, according to USA Today.

"There has been at least one instance where we've had to modify the route of one of our planes in order to maintain adequate airspace separation with a Russian aircraft," said Navy Capt. Jeff Davis, a Pentagon spokesman.

U.S. and Russian officials have met previously to discuss methods of avoiding any confusion between the two countries, but they have not thoroughly spoken about certain safety concerns.

The Russian plane came within a specified 20 nautical mile interval, but the U.S. and Russia have not agreed on procedural flying safety techniques, WTKR reported. The U.S. plane was reportedly not able to finish its mission, which highlights the Pentagon's desire to further discuss these issues with Russia. U.S. aircraft are still flying attacks and other missions daily over Syria, but they are cautious due to the presence of these Russian planes.

Russian warships began conducting airstrikes in Syria recently to fight against the Islamic State, according to the Daily Mail. The move follows the support that Syrian President Bashar Al-Asaad received from the Russian government and Vladimir Putin.