Britain is suffering from a "moment of psychological self-depression" before the Olympic Games begins, Boris Johnson has claimed.
The London mayor dismissed concerns about security and transport by claiming that both the UK and London were understandably nervous ahead of Friday's opening ceremony.
"I think possibly what we're going through now as a nation, as a city, is that necessary pre-curtain up moment of psychological self-depression before the excitement begins on Friday when the curtain goes up," Johnson told BBC1's The Andrew Marr Show.
"It is only natural that people should be tense, should be expectant and of course there are loads of things we need to get right."
The mayor said London's traffic and transport systems appeared to be "holding up" as the influx of people to the capital gathered pace.
But many fear Thursday's planned strike by immigration staff, on what is set to be the busiest day of the year at Heathrow, could lead to disruption which will damage Britain's reputation.
Only 20% of the Public and Commercial Services (PCS) union's membership took part in the vote on industrial action, which was backed by 57%.
The union is pressing ahead with the walkout in protest against the 20% spending cuts suffered by the Home Office.
"I don't think whatever they do it will disrupt the Olympics or our preparations or disrupt our ability to get people through safely and on time to their venues," Johnson added.
"I do think if you look at the numbers who voted to go on strike, it's a very badly supported strike."
PCS general secretary Mark Serwotka has said the lives of staff across the Home Office had been made "intolerable" by spending cuts, however.
"Ministers have known about these issues for a very long time and need to act now to sort out the chaos they have caused," he said.
"They're acting recklessly in cutting so many jobs and privatising services, and are provocatively refusing to talk to us with a genuine desire to reach an agreement."
Culture secretary Jeremy Hunt told Sky News' Murnaghan programme: "Surely this is a time not for promoting an industrial grievance but just putting the country first.
"I'm sure it's only a minority who really want to do this and I would just ask them to think again."