WASHINGTON (REUTERS) - President Donald Trump on Tuesday (March 20) congratulated Vladimir Putin on his re-election, a week after the United States took a harder stance toward Russia, and said they would likely meet soon to discuss the arms race and crises in Ukraine, Syria and North Korea.

Putin won a landslide victory in Sunday's presidential election, extending his rule over the world's largest country for another six years at a time when his ties with the West are on a hostile trajectory.

"I congratulated him on the victory, the electoral victory,"Trump told reporters at the White House while meeting Saudi Crown Prince Mohammed bin Salman.

"The call had to do also with the fact that we will probably get together in the not too distant future so we can discuss arms, we can discuss the arms race."

The White House later said there were no specific plans for a summit meeting.

Speaking of the arms race, Trump said: "We will never allow anybody to have anything even close to what we have."

Trump's administration last week accused Russia of hacking into America's energy grid and approved the first sanctions on Russian entities and individuals for alleged meddling in the 2016 US election.

The United States also joined Britain, France and Germany in demanding that Russia explain a military-grade nerve toxin attack in England on a former Russian double agent, with Trump saying last week: "It certainly looks like the Russians were behind" the incident.

Trump, who vowed to improve relations with Russia on taking office 14 months ago, has been under pressure from Congress, Democrats and Republicans alike, to take a tougher stance on Putin, his inner circle and scores of Russian oligarchs.

Republican US Senator John McCain chastised Trump for the congratulatory call.

"An American president does not lead the Free World by congratulating dictators on winning sham elections," McCain said in a statement.

"And by doing so with Vladimir Putin, President Trump insulted every Russian citizen who was denied the right to vote in a free and fair election to determine their country's future, including the countless Russian patriots who have risked so much to protest and resist Putin's regime."

SOFTER TONE FROM PUTIN

The Kremlin said Tuesday's conversation between the two leaders had been broadly constructive and focused on overcoming problems in relations, which are at a post-Cold War low.

"The leaders spoke in favour of developing practical cooperation in different spheres, including on questions of how to ensure strategic stability and fight international terrorism," the Kremlin said in a statement.

Moscow and Washington are at odds over Ukraine and Syria, while US allegations that Russia interfered in the US presidential election, something Moscow denies, continue to cast a shadow over ties. Trump has said there was no collusion between his presidential campaign and Russians.

Putin and Trump agreed on the need to work together to avoid a possible arms race, the Kremlin said, adding: "Special attention was devoted to working through the question of a possible high-level meeting."

Putin has struck a softer tone towards the West since winning his biggest ever election victory, saying he has no desire for an arms race and would do everything he could to resolve differences with other countries.

Kremlin spokesman Dmitry Peskov told Russian news agencies separately that Putin and Trump had not discussed the poisoning of former Russian double agent Sergei Skripal and his daughter in Britain. London has blamed Moscow for the attack, a charge Russia denies. The Skripals remain in a critical condition.

The White House said in a statement that the leaders"emphasised the importance of denuclearising the Korean Peninsula" after Trump agreed to meet North Korean leader Kim Jong Un in hopes of defusing the nuclear threat from the North.

Earlier on Tuesday, Russian Deputy Foreign Minister Sergei Ryabkov said he hoped Putin's win would persuade some US politicians to stop isolating Russia and said Moscow was open to dialogue with Washington, the RIA news agency reported.