France and Germany will leave Britain behind unless it becomes more positive about Europe, Robin Cook has warned.

As the EU summit in Greece continued, the former leader of the Commons claimed Germany had renewed its allegiance with France and could move ahead on key issues without Britain.

"Their recent pact to resist reforms to CAP demonstrates how damaging it is for Britain to be left out of the loop," he wrote in the Independent.

"The problem for Britain is that the rest of the convoy eventually wearies of proceeding at the pace of the slowest member."

Cook, who was Tony Blair's first foreign secretary, also attacked sections of the media for having "euro-paranoia".

"No doubt the editors of the eurosceptic press pride themselves on having stiffened the prime minister's resolve to insist on a good deal for Britain," he said.

"They have in the process also weakened his negotiating position by reinforcing doubts on the Continent whether Britain is really committed to the European enterprise."

Adding to his attack on euro-sceptics, he claimed their thinking was based on a bygone era.

"In the modern globalised world, sovereignty cannot possess the absolute, unlimited status that it enjoyed in the days of sailing ships and the telegraph wire."

On the day EU leaders debated the draft constitution, Cook said it was a diversion from the real issues that were disconnecting the public from Brussels.

"Europe will only restore its popular standing when it convinces the electorate of Britain and every other state that it widens job opportunities, cleans up the environment and guarantees stability," he added.