U.S. Defense Secretary Ash Carter, joined by U.S. Department of Defense press secretary Peter Cook (L)
U.S. Defense Secretary Ash Carter, joined by U.S. Department of Defense press secretary Peter Cook (L), arrives to speak to media on a military aircraft, July 19, 2015, en route to Tel Aviv, Israel, from Andrews Air Force Base, Maryland. Reuters/Carolyn Kaster/Pool

The United States and Russia signed an agreement on Tuesday to ensure air safety would be maintained when they conduct separate air strikes over Syria.

Last week, a Russian aircraft and a U.S. air vehicle entered the same battle space and came within a visible range of 20 miles of each other while conducting airstrikes in Syria. The Pentagon said that there was a complaint from Washington authorities that instead of attacking Islamic State fighters, the Russian airstrikes hit rebel forces that were fighting against Syria.

Russian airstrikes have reportedly killed more than 120 civilians since beginning their attacks over Syria on Sep. 30.

Pentagon Press Secretary Peter Cook said that Commander of U.S. Central Command Gen. Lloyd Austin signed the memorandum for the U.S. side. Cook said at the news conference that the U.S. has agreed to the request of Russia to keep the contents of the deal secret. The memorandum specified the U.S. and Russia keep a safe distance in Syrian airspace, though it was unclear whether the agreement contained a specified distance.

Russian news agency Ria Novosti reported that the agreement was signed by both Moscow officials and the U.S. authorities. “The Memorandum contains a range of rules and restrictions aimed at preventing incidents between the military aircraft of Russia and the United States,” Russian Deputy Defence Minister Anatoly Antonov said.

He also said that both countries’ military officials have agreed to establish round-the-clock communication channels and assure of mutual aid in the situation of a crisis.

“The Americans have promised to get the agreed rules to all participants of the anti-IS coalition they lead, so that their pilots proceed from those agreements,” the deputy defence minister said, referring to the countries participating in fight in Syria, including Australia, Canada, Jordan, Turkey, Bahrain, the United Arab Emirates, France and Saudi Arabia.

Contact the writer at feedback@ibtimes.com.au, or let us know what you think below.