Washington, Apr 14 (IANS): US President Joe Biden has urged Russian President Vladimir Putin to de-escalate border tensions with Ukraine and proposed the two leader hold a summit in the coming months, the White House said.

Biden spoke by phone with Putin on Tuesday to discuss a range of issues, from arms control to cyberattacks and fresh worries over the amassing of Russian troops on the Ukraine border, a statement said, DPA news reported.

The US president suggested their meeting take place "in a third country."

The last Russia-US summit was held in Helsinki in July 2018. At the time, then-president Donald Trump was embroiled in investigations over Russian interference in the 2016 presidential election.

In March, the Kremlin was outraged by Biden's comments about Putin during an interview. Biden had answered "I do" to the question of whether he considered Putin a "killer."

Kremlin spokesperson Dmitry Peskov said of the remark: "There has never been anything like it in history." He described US-Russian relations as "very bad" and accused Biden of showing no interest in improving the relationship.

The Biden administration recently imposed sanctions on Russia over the assassination attempt on jailed Kremlin critic Alexei Navalny.

Meanwhile, anxiety has grown over the recent build-up of Russian troops near Ukraine's borders.

During the phone call, Biden voiced "concerns over the sudden Russian military build-up in occupied Crimea and on Ukraine's borders, and called on Russia to de-escalate tensions," the White House said.

Reports of Russian military activity in and around Ukraine as well as ceasefire violations have sparked worries that the seven-year conflict between the two nations could escalate again.

Moscow annexed the Crimean peninsula after a controversial referendum in 2014. Western governments still consider Crimea to be part of Ukrainian territory.

NATO Secretary General Jens Stoltenberg on Tuesday said that "thousands" of combat-ready Russian troops have been moved to Ukraine's border.