Vladimir Putin has told Donald Trump in a new year letter that Moscow is ready for dialogue on a “wide-ranging agenda”, the Kremlin said.

The US president cancelled a planned meeting with his Russian counterpart at the G20 summit in Argentina in November, citing tensions about Moscow’s forces opening fire on Ukrainian naval ships and then seizing the vessels.

“Vladimir Putin stressed that [Russia-US] relations are the most important factor for providing strategic stability and international security,” the Kremlin said in a statement. “He confirmed that Russia is open for dialogue with the USA on the most wide-ranging agenda.”

In a separate letter to the Syrian president, Bashar al-Assad, Putin pledged to continue to support the country’s government and its people in the “fight against terrorism, in defence of state sovereignty and territorial integrity”.

Putin also sent new year greetings to other world leaders, including Theresa May, the Japanese prime minister, Shinzo Abe, and the Chinese president, Xi Jinping.

The Kremlin statement said Putin wished “wellbeing and prosperity to the British people”.

Russia’s embassy in London said on Friday that Moscow and London had agreed to return some staff to their respective embassies after expelling dozens of diplomats early this year.

Britain expelled 23 Russian diplomats over accusations that the Kremlin was behind the novichok attack in March on the former double agent Sergei Skripal and his daughter, Yulia, in Salisbury.

Russia denies any involvement in the poisoning and, in retaliation, sent home the same number of British embassy workers.