"In order for the denuclearisation of the [Korean] Peninsula to be verifiable and irreversible, a number of diplomatic and thereafter technical steps must now be taken," Mikser told ERR on Tuesday.

"President Trump clearly stated at the press conference that the loosening of sanctions can only follow once the nuclear disarmament process has truly become irreversible," the Estonian minister noted. "The goal is still the total nuclear disarmament of the peninsula."

Regarding the Americans' concessions, referring to what Trump had said, Mikser said that although the U.S. would love to bring its troops home and save money on large-scale military operations or exercises, it is still too early to discuss this at the moment. "Because this process must truly be clear, irreversible and tangible in order to be able to discuss the loosening of sanctions or the reduction of American military obligations in the region," he added.

According to the minister, Kim and Trump's meeting and joint declaration were a very symbolic and positive step which must be followed by a great number of more serious and detailed follow-up steps.

"Everyone expects that this political gesture of goodwill will be followed by steps based on which it can be said that the process has been set in motion," Mikser explained. "There is a set window of time here. If Kim Jong-un is serious, people want to see steps quickly. There have been false dawns in the past in connection with the Korean nuclear issue, where promises and signed obligations are unsuccessful."

Hanso: Japan watching closely

Chairman of the National Defence Committee of the Riigikogu Hannes Hanso (SDE) told ERR that Trump's promise to put an end to "war games" with South Korea because they were "very provocative" to North Korea is something that not a single previous U.S. president has said.

According to Hanso, neighbouring Japan is certainly interested in the easing of tensions in the region, however Trump's argument that maintaining a military presence and conducting exercises in the region is expensive is cause for serious strategic concern — "about whether the same calculation could hold true for Japan as well," he noted.

At their meeting in Singapore on Tuesday, Kim and Trump confirmed with the signing of a joint declaration their dedication to the total nuclear disarmament of the Korean Peninsula and promised joint efforts to establish a lasting and stable peace on the peninsula.