Petro Poroshenko spoke to the Times of London, while Dmitry Medvedev gave an interview to Russian state media.
The U.S. Navy has told Newsweek the footage was taken onboard USS Carl Vinson on Monday.
Kim Jong Un's visit to the clandestine site came as state-run media revealed images of the country's sixth missile launch this month.
"I would expect future port calls in Cuba and Venezuela, but more importantly, I would anticipate announcements on Russia-China military exercises, bilateral agreements and enhanced cooperation," a U.S. intelligence official told Newsweek.
On Monday, the U.S. Navy reported one of its fighter aircraft was involved in a "landing mishap" on the aircraft carrier USS Carl Vinson in the South China Sea.
"In the U.S. the question is 'Is Germany a reliable ally?' The question over in Europe is 'Is America going to be a reliable ally?'" the German Marshall Fund's Thomas Kleine-Brockhoff told Newsweek.
The Chinese Defense Ministry said joint drills "further enriched the connotation of the comprehensive strategic partnership of coordination between China and Russia in the new era."
The U.S. issued a similar order Sunday, warning: "military action by Russia could come at any time."
"Once the shots are fired, there is no putting the genie back in the bottle," former National Security Council Eastern European Affairs director Alexander Vindman told Newsweek.
"The interesting thing is that the wide variety of issues actually is closely intertwined," a Japanese official said after a meeting between Biden and Kishida.
But Airwars' Emily Tripp also said, compared to prior years, activists "haven't had that level of communication" and "haven't seen that level of interest" from the Pentagon to look into claims.
"Russia believes that weakness narrative, and not just about Biden, not even primarily about Biden, about the West, about the United States and Europe," Jeremy Shapiro of the European Council on Foreign Relations told Newsweek.
Kremlin spokesman Dmitry Peskov was responding to Biden's warning of "severe economic consequences" to Russian aggression in Ukraine.
Crisis Group's Brian Finucane told Newsweek he "would give the Biden administration a grade of 'incomplete' on winding down the U.S war on terror."
The test "confirmed the accuracy, safety, and operational effectiveness of this weapon system being produced," according to the North Korea's state news agency.
Previously, White House press secretary Jen Psaki said the Biden administration is concerned the Kremlin is preparing for "widespread human rights violations."
While Twitter permanently banned one account linked to Ayatollah Ali Khamenei, others remain active on the platform.
A State Department spokesperson told Newsweek that "the coming days" will prove if diplomacy can succeed, while Russia's envoy warned his country was on the "edge of the precipice."
"The U.S. Secret Service takes all threats to our protectees seriously," spokesperson Justine Whelan told Newsweek.
"It wouldn't be significant because of any of the results," former OFAC official Peter Kucik told Newsweek. "It would be significant because of the fact that it's fairly unprecedented to sanction a leader of the stature of Putin."
A propaganda video that included commentary in Chinese dialects widely spoken across Taiwan was viewed as a pointed warning to the island's population.
Chinese ambassador to Syria, Feng Biao, said the deal would "strengthen Chinese participation in the economic reconstruction" of the war-torn country.
"End that heinous jail," Cuban Foreign Minister Bruno Rodríguez Parrilla wrote in a social media appeal.
The test was "carried out with the purpose of finally confirming the overall technical characteristics of the developed hypersonic weapon system."
Kazakhstan's top diplomat said his country "is ready to have close communication with China to strengthen security cooperation and jointly combat terrorism, separatism and extremism."
Russia's U.S. ambassador said Kazakhstan's turmoil is rooted in destabilizing U.S. military intervention across Western and Central Asia.