The UK government has apologised to an Israeli minister who could not attend the COP26 summit on Monday because it was not wheelchair accessible.
Karine Elharrar tweeted that it was "sad" the UN "does not provide accessibility to its events".
An official in Israeli Prime Minister Naftali Bennett's delegation said they had formally complained to organisers.
And Mr Bennett said he would not attend on Tuesday if Ms Elharrar could not access the summit, the official added.
The UK's Environment Secretary, George Eustice, said the incident was "deeply regrettable" and the government had apologised to Ms Elharrar - who has muscular dystrophy.
But he also appeared to blame the Israeli delegation, telling BBC Radio 4's Today programme: "What would normally happen in this situation is that Israel would have communicated that they had that particular need for their minister.
"There was obviously something that went wrong in this instance and they weren't aware of that so they hadn't made the right provisions at that particular entrance she was coming too."
'Genuine mistake'
Ms Elharrar reportedly told Israel's Channel 12 that she could not get onto the grounds of the conference because the only options were to either walk or take a shuttle that was not suitable for a wheelchair.
Her office told the Times of Israel she waited outside the venue in Glasgow for two hours, and she was eventually forced to return to her hotel in the Scottish capital Edinburgh 80km (50 miles) away.
The organisers of COP26 told the BBC that the permanent structures for the conference were fully wheelchair accessible and the venue holds gold level accessibility status.
They also said they carried out a complete accessibility audit for the temporary structures, and they were deemed fully compliant.
A COP26 spokeswoman said: "This was a genuine mistake and we have apologised to Minister Elharrar -we look forward to her attendance at COP26 today [Tuesday].
"We remain committed to an inclusive event accessible to all and the venue was designed to facilitate that."
An official in the Israeli PM's delegation said Mr Bennett had told UK Prime Minister Boris Johnson about the incident, and Mr Johnson had invited Ms Elharrar to join a meeting between the two prime ministers on Tuesday.
