Parkrun writes to Prime Minister Boris Johnson warning a further delay to its return is now “likely” and that it is now “fearful for our future.”
Organisers say they face “significant and unjustifiable barriers” from a number of councils and have appealed to Mr Johnson for help.
The 5km events were meant to resume on 5 June but got put back to 26 June, with that date now in doubt too.
“Despite the government’s best efforts, Parkrun finds itself trapped,” it said.
Organisers need a significant number of landowners to give permission for races to return to avoid overcrowding at the mass participation event.
They said last month that 250 locations in England had given them permission to return, but that this fell “far short” of the number needed to prevent overcrowding at the areas given the go ahead.
Cabinet ministers Robert Jenrick and Oliver Dowden, London Mayor Sadiq Khan and World Athletics president Lord Coe have all backed the return of the event, which was suspended in March 2020 because of the coronavirus pandemic.
“We are deemed both legal and safe to return yet cannot do so because of uncoordinated and often unwarranted blockages by a number of local authorities who do not understand nor recognise the national framework,” continued the letter.
“We are a small charity and as a board we are fearful for our future. We need your help if we are to find a way through the added bureaucracy.
“It is clear that we need a significant intervention from the top of government to convince a few councils that their actions are inappropriate and that Parkun should be allowed to continue to benefit the mental and physical health of local communities in a safe and responsible manner.”