MOSCOW (AFP) - New reports emerged on Sunday of US spying efforts around the world as fugitive intelligence leaker Edward Snowden remained holed up in a Russian airport seeking an escape route to Latin America.

Snowden remained hidden in a Moscow airport transit zone for the 15th day on Sunday, but was back in the press with claims that the US National Security Agency (NSA) operated broad spying partnerships with other Western governments that are now complaining about its programmes and intercepted millions of phone calls and emails in Brazil.

Snowden told Germany's Der Spiegel that NSA spies were "in bed together with the Germans and most other Western states", in an interview the news weekly said was conducted before the 30-year-old former NSA contractor began his string of high-profile leaks last month.

In remarks published in German, Snowden said an NSA department known as the Foreign Affairs Directorate coordinated work with foreign secret services.

The partnerships are organised so that authorities in other countries can "insulate their political leaders from the backlash" if it becomes public "how grievously they're violating global privacy", he said.

Brazilian daily O Globo meanwhile reported that the NSA spied on Brazilian residents and companies as well as people travelling in Brazil, citing documents obtained from Snowden.

"Exact figures are not available, but last January, Brazil was just behind the United States, where 2.3 billion phone calls and messages were spied on," the newspaper said in an article co-written by Glenn Greenwald of the Guardian, the British newspaper that published Snowden's leaks on top-secret US surveillance.

O Globo said the documents described a programme called Fairview in which the NSA partnered with a major US phone company to gain access to the systems of overseas companies with which the US firm had relationships.

"The NSA used the Fairview programme to directly access the Brazilian telecommunications system. That access allowed it to collect detailed records of phone calls and emails from millions of people, companies and institutions," the paper said.

Brazil considers the allegation "extremely serious", foreign ministry spokesman Tovar Nunes told AFP.

The new reports came as Snowden faced the logistical nightmare of escaping Russia for a safe haven in Latin America after the leftist leaders of Bolivia, Venezuela and Nicaragua all offered him asylum.

All three have strained ties with Washington and represent Snowden's best options after his rejection by many of the 27 nations he had applied to for protection.

Washington has urged Russia to hand over Snowden as a gesture of good will because the two sides have no extradition agreement.

President Vladimir Putin - a former KGB spy who has often sparred with the White House during his 13 years in power - has flatly refused and suggested that Snowden had better quickly decide where he wants to go.

One of Russia's most senior lawmakers suggested on Sunday that Snowden should accept an offer extended to him by Venezuelan President Nicolas Maduro.

"Venezuela is waiting for an answer from Snowden," said parliament's foreign affairs committee chairman Alexei Pushkov.

"This may be his last chance to get asylum," he tweeted.

But Snowden's options at Moscow's Sheremetyevo airport are limited because the only flights to Latin America are routed through Cuba - a country that has remained conspicuously silent throughout the dispute.

Snowden also faces the risk of his plane being grounded by a European country, as happened to Bolivia's Morales when he was suspected of trying to smuggle the American from Moscow earlier this week.

All the flights to Cuba pass through the same European air space and there is no guarantee that a jet carrying Snowden would not be stopped and searched.

Snowden never boarded his plane out of Moscow for Cuba on June 24 for unexplained reasons.

Analysts said it was likely that he was simply not allowed to board by the Russians because he had no valid transit papers after his US passport was revoked.

Nicaragua meanwhile revealed details from Snowden's letter requesting asylum, in which he said it was unlikely he would receive a fair trial in the United States.

"I, Edward Snowden, citizen of the United States, am writing to seek asylum in the Republic of Nicaragua because of the risk of being persecuted by the (US) government and its agents" for revealing the existence of a vast US surveillance programme, he wrote, according to the Spanish language text of the letter to President Daniel Ortega.

"Under the circumstances, it is unlikely that I would receive a fair trial or appropriate treatment before trial," in which, he added, he would "face the possibility of life in prison or death." "He's dead, in a figurative sense," said French espionage historian Sebastien Laurent.

"Given the seriousness of what he has done, he will never find a safe haven."