Germany was Wednesday swept up in a wave of red, black and gold World Cup euphoria after its record 7-1 victory over Brazil, almost as though the mighty "Mannschaft" were already world champions.

"Unbelievable" and "speechless" wrote headline writers, the morning after the national team's stunning defeat of the hosts, sending hopes soaring for an end to the 24-year wait for a fourth World Cup title.

Shrugging off Tuesday's intermittent stormy weather, tens of thousands of fans at Berlin's city-centre "fan mile" had watched almost in joyful disbelief as their heroes scored seven times -- five of them in 18 madcap minutes in the first-half.

Waving flags or draped in the national colours as they erupted into cheers, fans held high T-shirts emblazoned already with "world champion".

Despite the World Cup final still being five days away and Germany's opponents not yet even decided between the Netherlands or Argentina, lines of cars noisily snaked through the streets of the capital with horns and music blaring, as other cities saw similar late-night celebrations.

Never normally lost for words, Germany's top-selling Bild simply splashed "There are no words" on its early-edition front page.

It devoted its first six full pages to close-up photos of German players from the stunning match with each scorer's name next to the order of their goals.

Die Welt described the game as "incomprehensible" and said "the whole football world is speechless", while news weekly Spiegel headlined "Germany's triumph: bang, bang, bang!".

'On to Rio'

Chancellor Angela Merkel, well known to be a football fan and often photographed in the stands with her arms in the air celebrating goals, will travel with President Joachim Gauck to Rio for Sunday's final, the president's office announced.

Her spokesman Steffen Seibert tweeted: "We are all on your side. Congratulations on qualifying for the final."

Foreign Minister Frank-Walter Steinmeier tweeted "What a game! On to Rio de Janeiro!" before -- diplomatically -- adding his thanks to the "great" Brazilian hosts.

"The best German performance ever in a World Cup!! Simply fantastic!!" tweeted 1990 World Cup winning striker Jurgen Klinsmann, who coached Germany to third place at the 2006 finals and saw his present side the United States beaten 1-0 by the Germans in the group stage.

Amid the jubilation and disbelief, several voices however cautioned against over-confidence.

"The chances are good for us," Interior Minister Thomas de Maiziere, who is also responsible for sport, said, on a visit to Italy, but adding: "Everyone should keep their feet on the ground."

International Olympic Committee chief Thomas Bach meanwhile pointed out that despite Germany's victory, the final would nevertheless start out at nil-nil.

"The team can be confident but not complacent," he said.

In a night of firsts, Germany's victory against Brazil attracted a record 32.6 million TV viewers in the country of around 80 million, the specialist media site Meedia said, making it the biggest-ever TV audience figure in the football-mad country.

And social networking site Twitter also beat all records of activity for a sporting event with a total of 35.6 million tweets sent during the match, smashing the previous mark set at the Super Bowl in February.

Many couldn't refrain from World War II references, including a jokey riff on the classic line from 1970s British TV series "Fawlty Towers" whose main character was played by John Cleese -- "Don't mention the Tor (goal)".