* Mixed messages from FIFA chief Blatter
* Brazil President promises "Cup of Cups" (Updates with Blatter quotes on Twitter)
By Brian Homewood
BERNE, Jan 6 (Reuters) - FIFA president Sepp Blatter cannot remember a World Cup host nation falling as far behind with their preparations as Brazil have, he said in an interview.
However, he later backtracked by tweeting that the tournament would be a success after Brazil President Dilma Rousseff said her country would stage the "Cup of Cups".
"Brazil has just found out what it means and has started work much too late," said Blatter in his interview with the Lausanne-based newspaper 24 Heures.
"No country has been so far behind in preparations since I have been at FIFA even though it is the only host nation which has had so much time, seven years, in which to prepare."
Rousseff reacted with a statement full of positive intent about the finals that start in June.
"The demand for tickets, the greatest for any World Cup, shows supporters in the whole world have confidence in Brazil," she said on Twitter.
"We love football and we will receive this Cup with pride and we will make it the Cup of Cups. The World Cup will be at home in Brazil as this is the country of football."
Blatter then also took to Twitter to say "Only 157 days to World Cup opening match in Sao Paulo. Preparations are in full swing in all 12 host cities. Brazil 2014 will be a success.
"I fully agree with @dilmabr (Rousseff) tweets today. The whole world, including me, is looking forward to the Cup of Cups. Brazil will be a great host."
Blatter has experience of nine World Cups, dating back to Argentina in 1978. He joined soccer's ruling body as a development officer in 1975 before becoming secretary general and then taking over as president in 1998.
Six of the 12 stadiums in Brazil missed the final deadline of Dec. 31 which FIFA set for them to be completed and put at the disposal of organisers.
They are the venues in Sao Paulo, Curitiba, Porto Alegre, Cuiaba, Natal and Manaus.
Many infrastructure and transport projects have been shelved or scaled back and organisers are still debating how to provide extra flights for the thousands of travelling supporters.
Brazil were elected unopposed as hosts in 2007 under the old rotation system which awarded the finals to South America.
The other nine South American countries had agreed to support Brazil as the only candidate in 2003, in effect giving them an additional four years to get ready.
Blatter also said he was resigned to further protests such as those that took place during last year's Confederations Cup.
"I am an optimist, not a pessimist. I am therefore not worried," he explained. "But we do know there will be protests again.
"The last ones during the Confederations Cup in this same country had their roots in the social networks.
"There was no specific goal, or a genuine demand, but during the World Cup the protests will perhaps be more concrete, more organised," said Blatter.
"But football will be protected, I don't believe that Brazilians will attack the football directly. For them it's a religion." (Additional reporting by Pedro Fonseca in Rio de Janeiro, editing by Tony Jimenez)