The US presidential administration has rejected a proposal to send American contractors to Ukraine to maintain F-16 and military equipment.

Sources of The Wall Street Journal said that the White House had refused because of security concerns.

The article points out that the debate on sending American civilians to Ukraine has become more critical with the arrival of the F-16.

The National Security Council considered sending contractors.

However, intelligence and others considered it too risky at this time, the sources said.

“Intelligence has expressed concern about the prospect of a Russian attack on American contractors in Ukraine,” the US official said.

Instead, the United States hopes that European countries will take on most, and possibly all, of the responsibility for aircraft maintenance.

At the same time, several representatives of the Department of Defense have called for sending repair specialists.

But Biden and his national security adviser, Jake Sullivan, were concerned that the Pentagon did not have adequate response plans in place in case these people were attacked by Russia.

The WSJ notes that without civilian American contractors to maintain the aircraft, Ukraine will have a hard time keeping the F-16s in working order.

However, it appears that sending Americans to Ukraine is still a red line for the White House, analysts say.

In August, it became known that the United States had reprogrammed the electronic warfare system on Ukrainian F-16s to counter modern Russian weapons.