U.S. President Donald Trump said that the Boeing 747 gifted by Qatar, which is being used as a temporary Air Force One, will soon be sent for additional upgrades after questions were raised about its security systems, Reuters writes.

According to Trump, the aircraft will receive the “maximum package” of upgrades, and the work will take about a month.

Trump began using the plane on July 1 after it was quickly refitted for presidential needs. The decision to carry out additional upgrades came amid experts’ questions about its security systems, including capabilities related to missile defense.