Belgium was among nine European countries to issue a joint statement on Friday following Donald Trump's announcement of the United States' withdrawal from the Open Skies Treaty.
This treaty allows aerial observation of armaments and military activities of the other states that have signed the treaty.
The United States accused Russia of not respecting the terms of the treaty, which has been signed by 34 countries, including NATO members.
"We regret the announcement by the United States government," the nine countries said in the joint statement. "We will continue to implement” the treaty and "will continue to dialogue with Russia" on its implementation, they added.
The letter was also signed by the Netherlands, Luxembourg, France, Italy, the Czech Republic, Spain, Sweden and Finland.
The countries acknowledge that they share concerns "regarding the implementation of the treaty provisions by Russia," but the text remains "functional and useful," they said. It has "obviously added value for our conventional arms control architecture and our common security."
"We will continue to dialogue with Russia as previously agreed (...) to resolve outstanding issues,” such as undue restrictions on flights over Kaliningrad. “We continue to call on Russia to lift these restrictions and continue our dialogue with all parties,” they said.
The Brussels Times