The projected date was hoped to be August, which would give time for a full season of league racing to be staged. Beginning in October would make finishing a league impossible.
The co-promoter of the Peterborough Panthers, Colin Pratt, said last week that he was working with the club landlords at the East of England Arena with the expectation that racing could resume before the summer was over. The announcement today means that Premiership racing won't occur this year.
Rob Godfrey, chairman of British Speedway Promoters Ltd, said: "We would like to offer our sincere appreciation for the supportive attitude shown to us from our broadcast partners Eurosport, they have been very understanding of this most difficult situation for the sport.
"Promoters up and down the country have worked 24/7 to try and give themselves every opportunity to stage league racing this season and I take my hat off to all those who have shown a positive attitude throughout.
"We have never given up and it is only the announcement from the Prime Minister on Friday that has left us with no choice.
"It is also important for us to thank all the riders who have remained patient throughout all of this, they have been left in an extremely difficult situation and our thoughts are with them all.
"In addition, the loyal sponsors throughout the country must also be acknowledged, their support is much appreciated by clubs.
"And we must also thank all supporters of this wonderful sport in this country. We must now embrace the future and look forward with a positive attitude as we look to grow British Speedway."