The start of the Premier League season this weekend is facing major disruption after its officials said they would decide tomorrow whether or not to call off the three opening fixtures set to take place in London following further rioting in the city.

Fulham versus Aston Villa, Queens Park Rangers against Bolton and Everton's visit to Tottenham, where the violence which has spread across the capital first erupted on Saturday, remain in the balance after a fourth day of violence, with the Premier League unwilling to confirm the games will go ahead until they have held further discussions with the clubs in question and the Metropolitan policeon Wednesday.

The Football League has taken the same stance, meaning all London-based games in the Championship, League One and Two as well could be called off. Fears are also growing that the disorder in London could impact on next summer's Olympic Games, with the Metropolitan Police Authority describing the situation in the capital as "extremely worrying".

The Premier League said that it would allow local police forces to make a final decision regarding the staging of this weekend's top-flight games but after the Football Association called off England's friendly with Holland at Wembley and West Ham, Charlton Athletic and Crystal Palace postponed their respective home Carling Cup ties with Aldershot Town, Reading and Crawley Town on Tuesday night for the same reason, it decided to take a more decisive stance.

"The Premier League and Football League are saddened by the recent incidents of civil unrest and the effect it is having on local communities," read a joint statement. "We are in on-going discussions with our London-based clubs, the Metropolitan police and statutory authorities in regard to the staging of the coming weekend's fixtures in the capital.

"The Metropolitan police has conveyed to us the dynamic nature of the current situation and with that in mind all parties will review the situation on Thursday and make a further public statement then."

The statement went on to say that "with the information currently available, there is no reason to think any matches outside of London will be affected", though clubs in cities that have also been hit by the riots, most notably Birmingham, Bristol and Liverpool, remain on alert. West Bromwich Albion said they are "monitoring what is an evolving situation" ahead of Manchester United's visit to The Hawthorns on Sunday and Bristol City also postponed their Carling Cup game with Swindon.

Somewhat oddly, while Bristol City's Carling Cup tie with Swindon last night was called off following advice from local police, Bristol Rovers' tie with Watford, scheduled for tonight, goes ahead, as does the club's League Two home fixture against Torquay on Saturday.

"We are not totally sure why this is the case, but believe it because Bristol City verses Swindon is a local derby and so would require a level of police resources that are just not available due to the problems taking place in the city at the moment," said a Rovers spokesperson.Meanwhile the International Olympic Committee said it was confident the Olympics would be secure but made clear responsibility for a safe Games lay with the British government and Metropolitan police. It said: "Security at the Olympic Games is a top priority for the IOC. It is, however, directly handled by the local authorities, as they know best what is appropriate and proportionate. We are confident they will do a good job in this domain."

Officials said there were no immediate plans to review security for the Olympics, which start next July, though there was an acceptance that London's image has been damaged and visitors may be deterred from attending the Games.

The assistant commissioner, Chris Allison, the national Olympic security co-ordinator, said: "Our planning for security is intelligence led. Public disorder is one of those risks which we have already been planning against across the country. Obviously, in light of the appalling events in London over recent days, we will review our planning to ensure that any lessons are identified. It is too early to say whether our planning will significantly change."

A test event was carried out, beach volleyball at Horse Guards Parade, but the finish was brought forward by 90 minutes to ensure it was completed in daylight and so avoid any riot-related trouble. Other test events to go ahead include the world badminton championships at Wembley Arena throughout the week, the Surrey Cycle Classic on Sunday, a test event for the cycling road race which will go through the streets of London, and the marathon swimming event at Hyde Park on Saturday.