Two Russian strategic bombers have landed in Venezuela as part of military manoeuvres, the Interfax news agency reported today, at a time when US-Russian relations are at their most strained since the cold war.

Interfax cited a Russian defence ministry statement as saying the two Tu-160 strategic bombers landed today to carry out training flights over neutral waters in the next few days before returning to Russia.

The arrival of the Russian strategic warplanes in what the US considers its backyard followed a statement at the weekend by the Venezuelan government saying that four Russian ships would participate in joint exercises in the Caribbean this year.

The US sought to make light of that announcement. A US state department spokesman, Sean McCormack, said that if Russia really intended to send ships to the Caribbean, "then they found a few ships that can make it that far".

Venezuela said a taskforce including four Russian naval ships and 1,000 Russian military personnel would take part in mid-November exercises with Venezuelan frigates, patrol boats, submarines and aircraft.

News of the planned exercise came shortly after Vladimir Putin, the Russian prime minister and former president, warned that Nato's deployment of several warships to the Black Sea in the aftermath of Russia's invasion of Georgia last month would not go unanswered.

The Russian agreement to send planes and ships could be seen as part of a campaign by the Venezuelan president, Hugo Chávez, who never loses an opportunity to take a jab at the US, to build up his military. Chávez has been on an arms-buying spree and has proposed a hemispheric South American defence council aimed at the US.

Thanks to high oil prices, Venezuela – a member of the Opec oil cartel - has been able to spend $4bn (£2.2bn) on weapons since 2004. Bought mostly from Russia, the arms included the purchase of 53 Russian helicopters and 24 Sukhoi fighter jets.

Venezuela is buying the rights and technology for a Kalashnikov assault rifle factory near Caracas. During a visit to Russia in July, Chavez said the two countries had formed a strategic partnership and he was buying a Russian missile defence system to thwart a potential US air attack.

Venezuela is reported to be considering buying as many as five diesel-powered Russian submarines. The deal would make Venezuela the region's top naval force.

Last year when he was still president, Putin said Russia would permanently resume long-distance patrol flights of strategic bombers, which were suspended in 1992 after the collapse of the Soviet Union. Since then, there have been several incidents in which British fighter planes have scrambled to intercept Russian warplanes.