Boris Johnson has clashed with Russia’s foreign minister over alleged cyberattacks on the West and activity in Ukraine.
Sergei Lavrov denied claims that Moscow had used the internet to interfere in democratic elections and accused Mr Johnson of being a “hostage” of untrue Western narratives on the issue.
After talks between the pair finished, they appeared to exchange barbs in a news conference on several issues and, at times, it grew tense.
At one point, Mr Lavrov told reporters Mr Johnson had told him that Russia did not interfere in the EU referendum.
“Not successfully,” Mr Johnson shot back.
“See, he has to say this so that he is not criticised back home, for his reputation,” Mr Lavrov responded.
“It’s your reputation I’m worried about, Sergei,” Britain’s most senior diplomat responded with a smile.
The UK’s Foreign Secretary insisted there was “abundant evidence” that Russia had attempted to influence polls in the US, Germany, Denmark and France.
Theresa May had earlier promised that Mr Johnson would take a “hard headed” approach to dealing with Russia when he travelled to Moscow for the first visit by a Foreign Secretary for five years.
After the talks, Mr Lavrov said London made a series of aggressive and insulting statements.
Mr Johnson was in Moscow in an attempt to open up communication channels after years of hostility.
He told Mr Lavrov before the talks got under way: “Things are difficult but we want to work together with you on some issues, Sergei, and we want to work to achieve a better future.
“We have a duty to work together for peace and security,” he added.
Afterwards, Mr Lavrov said the pair had discussed Libya, Yemen, Iraq, Syria and North Korea and had agreed to discuss the impact of Brexit on UK-Russia ties.
He said they had also discussed Ukraine, but failed to say if anything had been agreed, other than that the two countries needed to work together in the UN Security Council.
He said the both countries’ ability to tackle terrorism was constrained by the UK’s refusal to fully cooperate with the Russian security service the FSB.
Mr Johnson said the UK could not ignore events in Ukraine and Russian cyber activities and the problems faced by gay people in Chechnya and it was a sad truth that UK-Russia relations were going through a “very difficult patch”.
Mr Lavrov added, after mentioning the series of insulting statements, said he trusted Mr Johnson and was happy to call him by his first name.
“We are ready to develop dialogue on a very wide range of issues on the basis of principles of equality (and) taking into account and respecting each other’s interests,” Mr Lavrov said.
“We have to find a way forward,” added Mr Johnson.
The meeting comes a day after it emerged that a Ukrainian government translator who visited Downing Street with an official party has been arrested in Ukraine on suspicion of spying for Russia.
Later in the day, Russian President Vladimir Putin said Russia must strive to be a leader in building a “new-generation” army to protect its sovereignty and foreign policy, particularly near its borders.