U.S. Secretary of Defense Mark Esper has urged allies worldwide to increase their defense spending to at least 2 percent of gross domestic product, Kyodo cited the Defense Department as saying today, on Thursday. The remarks were in line with President Donald Trump's argument that allies should pay their "fair share." The president has repeatedly expressed frustration over the failure of members of the North Atlantic Treaty Organization to meet a target of spending 2 percent of their GDP on defense. "To our allies and partners around the world, know that we are committed to strengthening our relationships and preserving the international rules-based order," Esper said in a speech he made Wednesday at the Rand Corporation, a research organization created in 1948 initially to offer research and analysis for the U.S. military. "We urge you to increase your defense spending to at least 2 percent of GDP, and to make the needed investments to improve your capabilities and capacity, just as we are doing with our armed forces, to achieve our shared goals -- that is to protect our mutual interests, preserve our security, and defend our common values," he added, according to a transcript made available from the department.