MOSCOW — Russian President Vladimir Putin said Tuesday that the US and its allies have ignored Russia’s top security demands but added that Moscow remains open to more talks with the West on easing soaring tensions over Ukraine.

Putin argued that it’s possible to negotiate an end to the standoff if interests of all parties, including Russia’s security concerns, are taken into account.

“I hope that we will eventually find a solution, although we realize that it’s not going to be easy,” Putin said.

He deplored the Western refusal to consider the Kremlin’s demands for guarantees that NATO won’t expand to Ukraine, won’t deploy weapons near the Russian border and will roll back its forces from Eastern Europe.

The demands, rejected by NATO and the U.S. as nonstarters, come amid fears that Russia might invade Ukraine, fueled by the buildup of an estimated 100,000 Russian troops near Ukraine’s borders. Russia has denied having an intention to attack its neighbor, but talks between Russia and the West have so far failed to yield any progress.

The Russian leader charged that the Western allies’ refusal to heed Russia’s demands violates their obligations on integrity of security for all nations and insisted that a solution could be found through more talks.

He warned that Ukraine’s accession to NATO could lead to a situation where Ukrainian authorities launch a military action to reclaim control over Crimea or areas controlled by Russia-backed separatists in the country’s east.

“Imagine that Ukraine becomes a NATO member and launches those military operations,” Putin said. “Should we fight NATO then? Has anyone thought about it?”

Russia annexed Ukraine’s Crimean Peninsula in 2014 following the ouster of the country’s Moscow-friendly president and later threw its weight behind rebels in Ukraine’s eastern industrial heartland, triggering a conflict that has killed over 14,000.

Speaking after talks with Hungarian Prime Minister Victor Orban in the Kremlin, Putin emphasized that it’s still possible to find a settlement that would take every party’s concerns into account.

He said that French President Emmanuel Macron may soon visit Moscow as part of renewed diplomatic efforts following their call on Monday.

Orban, who has forged close ties with Putin, putting NATO member Hungary in a unique position, stressed that no European leader wants a war in the region and voiced hope for a settlement. The Hungarian leader has avoided taking a definitive stance on the buildup of Russian troops along Ukraine’s borders and some of his opponents at home criticized his trip to Moscow as a betrayal of Hungary’s interests and Western alliances.

In a bid to exert pressure on the West, Russian Foreign Minister Sergey Lavrov has sent letters to the U.S. and other Western counterparts to seek their explanations about past obligations signed by all members of the Organization for Security and Cooperation in Europe, a top trans-Atlantic security grouping.

Russia has argued that NATO’s expansion eastward has hurt Russia’s security, violating the principle of “indivisibility of security” endorsed by the OSCE in 1999 and 2010.

Putin charged that the West has “conned” Russia by reneging on its promises in the early 1990s that NATO will not expand eastward. He argued that the U.S. and its allies have ignored the principle that the security of one nation should not be strengthened at the expense of others, while insisting on every nation’s right to choose alliances.

Lavrov made the same argument in a phone call with U.S. Secretary of State Antony Blinken, saying that he warned that Moscow will not allow Washington to “hush it up.”

Blinken, meanwhile, emphasized “the U.S. willingness, bilaterally and together with Allies and partners, to continue a substantive exchange with Russia on mutual security concerns.”

State Department spokesman Ned Price noted that Blinken also “further reiterated the U.S. commitment to Ukraine’s sovereignty and territorial integrity, as well as the right of all countries to determine their own foreign policy and alliances.”

Blinken also “urged immediate Russian de-escalation and the withdrawal of troops and equipment from Ukraine’s borders,” Price said. He reaffirmed that “further invasion of Ukraine would be met with swift and severe consequences and urged Russia to pursue a diplomatic path.”

Senior State Department officials described the call as professional and “fairly candid,” noting that Lavrov restated Russia’ insistence that it has no plans to invade Ukraine and Blinken replied that if Putin didn’t really intend to invade Ukraine, Russia should withdraw its troops. The top diplomats agreed that the next step would be for Russia to submit its response to the U.S. and for the sides to speak again.

Shortly after speaking to Lavrov, Blinken convened a conference call with the secretary general of NATO, the EU foreign policy chief and the chairman-in-office of the OSCE as part of efforts to ensure that the allies are engaged in any further contacts with Russia.

High-level diplomacy continued Tuesday, with British Prime Minister Boris Johnson arriving in Kyiv for scheduled talks with Ukrainian President Volodymyr Zelenskyy.

Addressing Zelenskyy, he noted that “more than 100,000 Russian troops are gathering on your border in perhaps the biggest demonstration of hostility toward Ukraine in our lifetimes.”

Johnson said the U.K. has a package of measures including sanctions ready to go “the moment the first Russian toecap crosses further into Ukrainian territory.”

“It is vital that Russia steps back and chooses a path of diplomacy and I believe that is still possible,” Johnson said. “We are keen to engage in dialogue, of course we are. But we have the sanctions ready.”

Earlier Tuesday, visiting Polish Prime Minister Mateusz Morawiecki promised to deliver more weapons to Ukraine, including portable air defense systems, drones, mortars and ammunition, noting that Russia’s neighbors feel like they are living “next to a volcano.”

Zelenskyy said Ukraine would forge a new trilateral political alliance with Britain and Poland, hailing it as a reflection of strong international support for Ukraine.

The Ukrainian president signed a decree on Tuesday expanding the country’s army by 100,000 troops, bringing the total number to 350,000 in the next three years, and raising army wages.

The decree ended conscription starting from Jan. 1, 2024, and outlined plans to hire 100,000 troops over the next three years.