LIZ Truss’s latest foray into international diplomacy has not gone to plan after she was given a lesson in basic geography.

The UK Foreign Secretary was mocked by Maria Zakharova, Russia’s foreign ministry spokesperson, for failing to know the difference between the Baltic and Black seas, which are more than 700 miles apart.

It came as another senior Kremlin official dismissed British diplomacy as “absolutely worthless”.

Truss, who is due to travel to Moscow once she recovers from coronavirus, told the BBC’s Sunday Morning show that “we are supplying and offering extra support into our Baltic allies across the Black Sea”.

Zakharova noted that the Baltic nations of Estonia, Latvia and Lithuania lie off the Baltic Sea, not the Black Sea, which is hundreds of miles to the south.

“The Baltic countries are called so because they are located precisely off the coast of this [Baltic] sea. Not the Black [Sea],” the Russian official wrote on Facebook. “If anyone needs to be saved from anything, then it is the world from the stupidity and ignorance of Anglo-Saxon politicians.”

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Meanwhile, Dmitry Polyanskiy, Russia’s deputy ambassador at the United Nations, also criticised Johnson’s government.

He told Sky News: “There is always room for diplomacy but, frankly, we don’t trust British diplomacy. I think in recent years British diplomacy has shown that it is absolutely worthless.

“I really don’t want to offend anybody, especially my good friends, British diplomats, but really the results are nothing to boast about.”

The National: Unimpressed: Russian foreign ministry spokeswoman Maria ZakharovaUnimpressed: Russian foreign ministry spokeswoman Maria Zakharova

Truss, who spoke to her Ukrainian counterpart on Wednesday, has stressed the UK’s “unwavering” support for Ukraine as US President Joe Biden is set to send troops into European countries to support the former Soviet state.

Foreign minister Dmytro Kuleba and Truss agreed “responding decisively and strongly to the Kremlin now will help deter future as well as present Russian aggression”, a Foreign Office spokesperson said.

They said: “Both agreed that European and Nato allies need to present a robust and united front to Russia.”

No 10 insisted “our strong preference remains that Vladimir Putin pursues diplomatic efforts” to dial down threats to Ukraine’s sovereignty.

But the Prime Minister has warned there were no signs that the Kremlin was looking to de-escalate the situation.

Putin has said he does not intend to order an invasion, but there are more than 100,000 Russian troops on Ukraine’s eastern border, backed by tanks, artillery, helicopters and warplanes.

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While a senior US official confirmed the country is sending about 2000 troops to Poland and Germany this week and roughly 1000 more who are already based in Germany will go to Romania.

In the UK, Downing Street said it has a package of sanctions ready that will “severely” hurt Russia’s economy should Moscow order troops across the Ukrainian border.

The Prime Minister’s official spokesperson told reporters: “We don’t preview what the sanctions package might be.

“I think the Prime Minister was very clear yesterday about the automaticity of our sanctions package that we have ready to go.

“It will severely damage the economy of Russia and, as the Foreign Secretary made clear, be targeted as well at the Russian elite, but beyond that I’m not going into it.”

The No 10 spokesperson added: “We do have a package of sanctions ready, we’ve been working on that with our Nato allies, so we have both discussions with Nato allies and we have our own approach as well.

“So, we are ready to act but, vitally, it is important our strong preference remains that Vladimir Putin pursues diplomatic efforts.”