The Russian air force has not shown any good faith toward NATO aircraft policing Baltic airspace in recent months by conducting a flurry of unsafe maneuvers and flybys, the top civilian leader of the Air Force said Monday.

Air Force Secretary Deborah Lee James said the German air force, which oversees the mission, reported “more than 30 scrambles between the end of August and the start of November this year, intercepting Russian aircraft flying near civilian air routes with their transponders turned off.”

And through this year, the Russian air force intercepted U.S. Air Force and Navy pilots at least four times. Most notable was when a Russian Su-27 barrel-rolled over an Air Force spy plane over the Baltic Sea in April, she said.

The incidents highlight why it’s important for NATO countries, especially the “newer partners,” to continue joint training — even amid budget challenges and a fighter pilot and maintainer shortage in the U.S., James said at a talk hosted by the Atlantic Council in Washington, D.C.

The secretary said NATO members should work quickly to contribute at least 2 percent of their gross domestic products on defense spending — a rule proposed by the bloc in 2014. Only five countries currently meet the standard — the U.S., United Kingdom, Poland, Greece and Estonia, according to the organization’s own information.

President-elect Donald Trump has criticized the U.S. for acting as the backbone to the NATO alliance, and left the door open on whether he would defend countries he deemed as not properly contributing. Trump beginning this summer questioned the automatic defense of NATO states and suggested the U.S. would provide aid only if they “have fulfilled their obligations to us.”

Even so, the Air Force’s obligations to the Baltic countries — which lack capable air forces — will continue in 2017 in part under the newly rebranded European Deterrence Initiative, James said, “to reflect that our presence … does more than reassure.”

The funding — supported by both Congress and President Barack Obama to keep Russian forces at bay with various missions, exercises and aircraft deployments — is slated to increase exponentially from $789 million in 2016 to $3.4 billion in 2017.

The Air Force plans to send F-15 Eagles from the Louisiana and Florida National Guard to various locations in Europe in the latest example of the ongoing effort, James said. Since the annexation of Crimea in 2014, the Air Force has deployed aircraft, from F-15s to A-10s ground-attack aircraft, as part of a regular rotation of assets meant to deter Russian aggression on the continent.

Europe’s hunger for fifth-generation fighters such as the F-35 Joint Strike Fighter, as well as surveillance aircraft is obvious and something the Air Force can’t ignore, James said.

After being approved to fly initial operations in August, the Lockheed Martin Corp.-made F-35 will be ready to deploy to the European theater next summer in line with how “allies expect it will transform the battlefield, even in the … anti-access area denial environment,” she said.

In areas like Kaliningrad near the Baltic Sea, Russian forces have prepositioned ballistic missiles to deter allied aircraft.

Since becoming the secretary in 2013, James has met with 19 of the 28 NATO countries and sought to improve relationships with such countries as Sweden and Finland. The secretary said she learned all partners “want more U.S. Air Force — more training, more exchanges, more presence, more interoperable equipment.”

To pool resources, James said NATO is acquiring a handful of RQ-4 Global Hawks as part of the alliance ground surveillance system to be based in Italy. Roughly 600 personnel will keep them flying and should be delivered before January, Defense News reported.

The Northrop Grumman-manufactured high-altitude drones “will enhance capabilities to support protection of ground troops and civilian populations in conflict environments as well as border control and maritime security,” she said. “Presence, joint training and political resolve are extremely important at this point in time.”

James described the Pentagon’s response to Russian aggression in the region as a success because “we haven’t seen another repeat of what happened in Crimea, so I think that’s very important.”

She added, “I’ll just repeat what [Baltic nation leaders] have told me, they certainly view these actions as a major deterrence. But again…our allies would like to see more.”