He said the deployment was a case of “two corrupt governments squandering public funds, and squelching liberty and freedom while their people suffer”.

President Vladimir Putin’s spokesman Dmitry Peskov said “this is of course highly undiplomatic of the secretary of state” and called Pompeo’s tweet “unacceptable”.

Answering the accusation of squandering funds, Peskov said: “We don’t agree with this, what’s more it’s probably not very appropriate for a country to make such statements when half its defence budget could feed the whole of Africa.”

Foreign ministry spokeswoman Maria Zakharova attacked what she called US “hysteria” over the planes.

“Just two planes and the State Department gets hysterics. Colleagues: you shouldn’t stress out so much,” she wrote on Facebook.

The Russian foreign ministry in a later statement said that “such clear neglect of the norms of diplomatic etiquette cannot be considered a run-of-the-mill incident.”

“What the Secretary of State said is unacceptable, not to mention completely unprofessional.”

The ministry urged the US to “count the money in its own pocket” instead of criticising Moscow’s decisions, referring to the US spending its “colossal military budget” on campaigns in Afghanistan, Iraq and Libya.

Russia sent about 100 pilots and other personnel along with two Tupolev-160 bombers and two other aircraft to Caracas.

The commander of the Russian air force’s long-range aircraft, General Sergei Kobylash, said the exercises “will help us understand better how Venezuela’s pilots are organised and trained (and) share our experience with them.”

Russia sent the planes following a visit to Moscow last week by Venezuelan President Nicolas Maduro for talks with Putin, who expressed support for the beleaguered socialist government.