Western countries could provide the Ukrainian air force with jets and pilot training, according to the U.S. Air Force.

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During an interview at the Aspen Security Forum, Air Force Gen. Charles Q. Brown said there are a number of different platforms that could go to Ukraine, including jets made by the United States, Sweden, France or the multi- country Eurofighter consortium.

Getting spare parts for Russian-made fighter jets could prove difficult, so Brown said any warplanes transferred to Ukraine will probably be something non- Russian.

The process of training Ukrainian pilots to fly Western jets could take months according to Brown and other experts.

The military hasn't decided whether to start training Ukrainian pilots yet, but "we do examine a wide variety of options."

In the last few months, the United States has increased its military support to Ukraine. Logistical challenges and fears that Russia could view the move as NATO involvement in the war have made the Pentagon hesitant to fulfill Ukrainian requests for fighter jets. The Polish military would give some of its Soviet-era jets to the Ukrainian air force in exchange for used American-made aircraft from the United States. The U.S. military quickly scuttled the idea, with John Kirby arguing that Russia may see the trade as an escalation.

A total of $7 billion. According to the Department of Defense, the United States provided military assistance to Ukraine from the beginning of the Russian invasion to early July. Thousands of anti-tank and anti-aircraft systems, hundreds of Switchblade drones, several Russian-made helicopters and HIMARS precision-guided rocket systems are included.