The US Department of State believes that the US armed forces are the strongest ever in the human history, spokesman John Kirby said, commenting on the Russian president’s words that Russia is stronger than any aggressor.

"I don’t think in all of human history there has ever been a military as capable and as intelligent, as strong, as well-led, as well-resourced, as the United States military is today," the spokesman told reporters Thursday.

"I think the professionalism and the skill and the capabilities that are resident in the United States military are beyond debate and dispute," he added.

Russian President Vladimir Putin the Defense Ministry board meeting earlier in the day that Russia is stronger than any potential aggressor, but warned that there was no time for the military to relax and let its guard down.

"There is still much work to be done, but taking into account our achievements, not only military ones, but also our history, geography, the state of the Russian society - we can say with confidence that at present we are stronger than any potential aggressor, Any!" Putin said.

However, he added that "If we let ourselves relax even for a minute, delay the modernization of the armed forces or military training, the situation may change in no time."

"Given the rapidly changing situation in the world, we will not have the time to notice it," the president warned.