McLaren boss Martin Whitmarsh has called for further improvement from his team if they are to win this year's world championship.
He made his call in spite of McLaren taking a second successive one-two victory at the Canadian Grand Prix on Sunday.
Lewis Hamilton, champion in 2008, led his McLaren team-mate and defending drivers' champion Jenson Button to victory in a thrilling race at the Montreal circuit.
However, Whitmarsh has warned that Red Bull are still the team to beat and that they should not write off rivals Ferrari or Mercedes.
Hamilton, 25, now leads the drivers' championship with 109 points, Button, 30, is three points behind, with 33-year-old Australian Mark Webber of Red Bull a further three points adrift.
Sunday's victory also extended McLaren's lead in the constructors championship to 22 points over rivals Red Bull. Ferrari trail in third a further 32 points back.
Whitmarsh, though, insists the title race is still wide open and is hoping for some major upgrades to the McLaren car ahead of the British Grand Prix in July.
"It is a classic case that if we don't develop the car at a quick enough pace then we will not win races," said Whitmarsh.
"We have got an underlying development programme, and we are trying to bring 0.15 to 0.25 seconds off every race. We won't stand still. We have a reasonably big upgrade that we are fighting to have for Silverstone, and if that is there then I would be disappointed if it is not a much bigger step than that. But I also expect, Red Bull Racing to fight back."
Whitmarsh expects Red Bull to come back with a vengeance but is confident that his team have the experience to deal with the situation.
"We are quite a battle-hardened team whose team has won four races so far this year," he said.
"We have been through a lot of world championship fights and we have probably got a bit more experience in our team than Red Bull but we don't underestimate them. They are going to come back strongly, for sure, and we have to make sure that we continue to develop the car."