Mark Webber, runaway championship leader Sebastian Vettel's teammate, told Auto Motor und Sport that Ferrari's winning pace in Britain was "no fluke".
"We can assume that this was not the only Ferrari victory for the year," said the Australian.
"We can't make excuses for Silverstone -- even our KERS worked flawlessly," admitted Webber.
Spaniard Alonso is bullish about the recent improvements to his Ferrari and is not completely writing off his chances.
"If we manage to put Red Bull under pressure they can make mistakes," he is quoted by Speed Week, "and then anything is possible."
But Spanish and Italian reports quote him as adding: "To talk about the world championship with this (points) gap would be to not understand formula one."
Alonso said his strategy is therefore simple.
You have to risk in every qualifying and every race and hope for Red Bull to make mistakes
"You have to risk in every qualifying and every race and hope for Red Bull to make mistakes. If it was my advantage I would play more cautiously, but now I can only attack."
Triple world champion Niki Lauda agrees that it would be wrong for Ferrari to give up and switch is full focus to 2012.
"Absolutely, it's still too early," the great Austrian told Die Welt.
"No matter what happens now, I predict Sebastian will win the title three races before the end of the season."