The group of Ukrainian pilots has been participating in an English language program at the Defense Language Institute English Language Center at Lackland, said Air Force spokesperson Rose Riley.

“Testing will determine their next courses and when the pilots would be able to commence F-16 training. Training location options are still being considered at this time,” Riley said.

The news comes as the U.S. announced on Wednesday that it will head up a coalition of countries training Ukrainian pilots and crew to operate and maintain the F-16s, alongside the Netherlands and Denmark. So far, 11 countries have signed up to help with the training, while the Netherlands, Denmark and Belgium will donate aircraft.

During a press conference in Brussels earlier this week, Defense Secretary Lloyd Austin said the F-16s would arrive on the battlefield next spring at the earliest.

The training begins amid concerns that the Pentagon is running out of money to continue sending military aid to Ukraine, after lawmakers passed a last-minute spending bill to avert a government shutdown that did not include funding for Kyiv. And it comes days after Hamas militants launched a surprise attack on Israel, sparking a conflict that has rocked the region.

Officials in Kyiv have been pushing to get modern fighter aircraft to the battlefield for more than a year. The Ukrainian military, working with DOD, has managed to integrate Western air-launched missiles with its Soviet-era fighter jets, according to one of the U.S. officials, an effort Politico reported was ongoing in March. However, Ukrainian officials say modern fighter jets will give them an advantage.

President Joe Biden finally approved an international effort to train Ukrainian pilots to fly F-16s in May, but the coalition took months to straighten out the details of the program. Initially, officials said the pilots and maintainers would train in Europe; the Pentagon announced last month that some of the training would take place in the U.S.

A group of Ukrainian pilots training in Europe are already learning on F-16 flight simulators, Ukrainian Air Force spokesperson Yurii Ihnat said earlier this month. The next stage is “flights with an instructor in real jets,” he said.