Hamilton title on loan - Montezemolo

Lewis Hamilton's Formula One title is only on loan, Ferrari president Luca di Montezemolo said after the season-ending Brazilian Grand Prix.

"I would like to send my congratulations to Lewis Hamilton, the youngest ever world champion in the history of Formula One," the Italian said in a statement.

"He was a very powerful rival indeed and his win, close though it was, was well deserved.

"He'll have the number one on his car next season, but he can rest assured of one thing: we'll be doing our very best to put it back on a Ferrari."

McLaren's Hamilton, 23, won the title by a single point from Ferrari's Brazilian Felipe Massa after overtaking Toyota's Timo Glock only seconds from the end of the last lap of Sunday's race at Interlagos.

Ferrari lost the 2007 drivers' title won by Finland's Kimi Raikkonen but retained their constructors' crown.

Montezemolo said that, in all his years in Formula One, he had never seen a more exciting finish and congratulated his team for their efforts in winning the title for a record 16th time and eighth in the past decade.

"Winning for the eighth time in 10 years - a feat unequalled at world level in any other team sport - proves beyond a shadow of a doubt what an extraordinary group we are," he said.

"Felipe, in particular, is in my thoughts as he crossed the finish line on Sunday as world champion only to see the title slip through his fingers a few seconds later. I can only imagine how painful that moment must have been for him."