Mark Zuckerberg has turned down another yet another request to answer questions from politicians outside of the United States.

On October 31st, the Facebook founder was invited to give evidence before a UK parliamentary committee, with politicians from Canada co-signing the invitation. This unusual show of international cooperation has since been supported by lawmakers from Australia, Argentina, and Ireland, with these five countries forming an “international grand committee” representing some 170 million Facebook users.

Zuckerberg rejected the request on November 2nd, according to UK MP Damian Collins, who made the original invitation in his role as head of the country’s Digital, Culture, Media and Sport select committee. In a letter published today, Collins said he and his Canadian counterparts were “very disappointed with [Facebook’s] dismissive response.”

“Mark Zuckerberg has set himself the personal challenge of ‘fixing’ Facebook this year to prevent its misuse in our democratic process,” said Collins in an earlier statement. “By being unwilling to face questions about his progress, doubts about his ability to do so remain.”

Zuckerberg has only given evidence to Congress and the European Parliament

Zuckerberg has already rejected two requests to give evidence in the UK, and has so far only spoken personally to three legislatures: the US Congress, US Senate, and European Parliament. Facebook has explained Zuckerberg’s refusal to speak by saying he does not have time to talk to every country’s lawmakers. (Hence the international appeal.)

This latest committee will meet in London on November 27th regardless, with Collins chairing the event. The aim of the committee is to analyze the spread of fake news and misinformation, with the UK and Canada preparing independent reports on the topic.

In his latest letter, Collins and his fellow politicians repeated their exhortation for Zuckerberg to attend. “We say again: the hearing of your evidence is now overdue, and urgent [...] We call on you once again to take up your responsibility to Facebook users, and speak in person to their elected representatives.”