Diamond League events in Paris and Eugene, Oregon, became the latest on the coronavirus-ravaged athletics calendar to be scrapped on Friday.
The Paris meeting had originally been pushed back from June until 6 September but was ultimately called off by organisers due to doubts over global travel and a lack of time to prepare a "world-class international event".
The Prefontaine Classic in Eugene, scheduled for 4 October, was also axed from the programme, with restrictions still in place to combat the Covid-19 pandemic in the west coast state.
"The state of Oregon currently has a ban on large gatherings - including sporting events - and that restriction will be in place until at least the end of September," Diamond League organisers said in a statement.
"The ban, combined with the expected long term restrictions on international travel, make it impossible to host a world class track and field meet... on 4th October."
Eugene will host the world athletics championships in 2022. The competition was moved back a year to accommodate the postponement of the Tokyo Olympics.
Four of the 15 Diamond League meetings have been cancelled, with Rabat and London also binned.
The circuit is due to start 14 August in Monaco followed by the Stockholm meeting nine days later.
The Gateshead event in northeast England could now be held 12 September but is still to be confirmed, organisers said.
"Final confirmation cannot be given at this time due to UK Government guidelines and restrictions," the statement said.