Russia's foreign ministry has said British threats to boycott the 2018 World Cup over the poisoning of secret agent Sergei Skripal will damage both the relationship between the two countries and world sport.

Skripal, 66, and his 33-year-old daughter, Yulia, remain in a critical condition after they were exposed to what U.K. authorities have described as a "nerve agent" in the English city of Salisbury earlier this month.

Last week, U.K. foreign secretary Boris Johnson said that "it will be very difficult to imagine that UK representation [at the World Cup] will go ahead in the normal way" if Russian involvement was proven. And on Monday, British Prime Minister Theresa May said that Russian involvement in Skripal's poisoning was "highly likely."

Sources have told ESPN FC there are no plans for the English Football Association to hold talks regarding any potential boycott, but the foreign ministry for this summer's host nation responded with criticism to the prospect of any withdrawal by the England national team.

"Such proposals [to boycott the World Cup] come not only from journalists, but also from officials -- in particular from U.K. Foreign Secretary Boris Johnson and from the Chairman of the Foreign Affairs Committee Tom Tugendhat," the Russian foreign ministry told news agency Interfax.

"Skripal's poisoning, for which the investigation has not even begun yet, is being used by British politicians to draw conclusions about Russia's involvement. So now they want to 'punish' us with a World Cup boycott.

"At the same time, even they [the U.K.] do not seem to have decided yet: who should boycott the World Cup -- the members of the royal family, government or the England national football team?

Russia will get the 2018 World Cup underway when the host nation faces Saudi Arabia in Moscow on June 14. Sergei Savostyanov\TASS via Getty Images

"We want to emphasise once again that such provocative statements that fuel anti-Russian hysteria, only complicate relations between our countries and are a blow to the sport.

"We have repeatedly warned that before the start of the World Cup in Russia, the Western media will launch a full-scale media campaign to discredit Russia and undermine its credibility as hosts.

"As we expected, the English are especially active in this, they cannot forgive Russia for winning the rights to host the 2018 World Cup instead of them, which was a fair decision after a fair election. Now the British media are actively calling for a boycott of the upcoming World Cup."

The vice-president of the Russian Football Union, Nikita Simonyan, also commented on the matter, saying that the poisoning incident should not affect the hosting of the World Cup in Russia.

"Not long ago they [the U.K.] said that sport must stay out of politics, and now here we are again," Simonyan told Interfax. "Should England refuse to participate, followed by Poland, Japan, Australia, it will not be a weaker World Cup, their seats are likely to be occupied by those who took second place in the qualifying groups."

Simonyan also added that the refusal to participate in the World Cup could threaten the relationship between countries. However, he called for calm and said they will only "hear the statements of Theresa May and the minister of foreign affairs."