One of the largest artificial intelligence and machine-learning conferences in the world kicks off in Montreal this weekend, but major researchers are still waiting to hear if the federal government will grant them the visas they need to attend.

Academics from institutions including the Massachusetts Institute of Technology (MIT) and the University of Oxford have yet to hear if their visas, which in some cases they applied for months ago, will be granted.

“Canada taking over 2 months to issue visas for PhD students trying to go present their work at Neural information Processing Systems — total disappointment, causing many people to miss out on participating. Maybe next time we should have the conference in a more friendly place!” tweeted MIT professor Suvrit Sra.

The Neural Information Processing Systems (NeurIPS) conference expects about 8,300 attendees at its 32nd annual event, which runs from December 2 to 8. Major companies including Apple, Alibaba, Amazon and Facebook are scheduled to attend; top Canadian researchers including Google’s Geoffrey Hinton and Element AI’s Yoshua Bengio will present their work.

The government said it’s trying to assist attendees with last-minute visa approvals. “We will work to provide any help that we can,” Danielle Keenan, press secretary for Innovation Minister Navdeep Bains, told The Logic.

Some researchers, however, have already cancelled their travel plans. Chip Huyen, a deep-learning engineer at Nvidia, a California-based chipmaker, tweeted that she is no longer attending the conference and has “asked a colleague to step in for me for a talk because I still have no update about my visa.” Natalia Efremova, a research fellow at the University of Oxford, also cancelled her travel plans, saying, “If a [University of Oxford] researcher cannot get a visa I can only imagine how many people were affected by visa issues.”

Terrence Sejnowski, president of the NeurIPS foundation, which organizes the annual conference in different cities around the world, said it’s “not unusual” for attendees to have visa issues, but that the conference doesn’t track how many attendees are having problems.

“We understand that several prominent members of our community have made personal appeals to the Canadian government on this issue. We wish all of our colleagues best of luck in navigating their visa applications,” said Sejnowski.

“While it is up to government agencies to decide on visa applications, we hope officials will appreciate the importance of facilitating the free flow of open science, something very important for AI and key to making sure the technologies that evolve from this research are beneficial for all.”

The problem, according to a senior government official who spoke on the condition of anonymity, is that the government only received a complete list of potential NeurIPS attendees on Monday.

“This is a top priority for us and we’re working as fast as we can to get people processed but up until a few days ago we were significantly limited in what we could do,” said the official.

Immigration, Refugees and Citizenship Canada received a list with the names of about 7,000 researchers who had signed up to attend NeurIPS a month ago but it was only on Monday that it got a list containing the dates of birth of attendees, according to the government official. Without dates of birth, it’s difficult for the government to know whether, for example, someone named John Smith is the same John Smith on the list to attend NeurIPS, or just someone else with the same name.

NeurIPS organizers said the government asked them for a list of dates of birth and passport numbers for their attendees, but they were unable to give it to the government because they don’t keep that information.

“We do not retain people’s date of birth or passport number in order to protect their security. This was communicated,” said Mike Mozer, a board member of the NeurIPS foundation. “We first sent requested immigration information to officials that we were able to provide on October 26th [and] we have been in open and constant communication with them since.”

Senior government officials, including Bains and Prime Minister Justin Trudeau, have spent much of the past two years touting Canada as an AI powerhouse. On December 6, Bains will host a G7 conference on AI in Montreal.

“Artificial Intelligence is a key part of our government’s economic growth strategy. It presents new opportunities to generate prosperity for Canadian families through new and innovative high-quality jobs,” said Bains in a press release announcing the G7 event.

Despite that high-level government support, NeurIPS isn’t the only Canadian AI conference for which attendees have had visa difficulty. Researchers trying to attend the Self Organized Conference in Machine Learning (SOCML) at Google’s Toronto office, which begins Friday, have also had problems.

Patrick Sikalinda, co-founder of the Zambia-based agricultural AI company AgriPredict, said his first visa was rejected because Canadian immigration officials thought he would stay in Canada after his visa expired. A letter from Google accompanying his application, which The Logic has seen, states that Sikalinda will be in Canada for “approximately four days.” He applied for a second visa four weeks ago and has yet to hear back on whether it has been approved.

Graeme Moffat, a senior fellow at the University of Toronto focusing on innovation policy, told The Logic that many conferences that used to be held in the U.S. have migrated to Canada in recent years. Collision, which bills itself as “North America’s fastest-growing tech conference,” will be held annually in Toronto from 2019 to 2021, the first time it’s being hosted outside the U.S.

“There’s a huge window of opportunity for Canada to become a default stop on the conference tour,” said Moffat.

“If Canada doesn’t step into the void and do a better-than-half-ass job of processing scientists’ visas, it’s not clear who will.”

Researchers from African countries have faced particular issues getting visas to attend the Black in AI workshop, which will be held on the sidelines of NeurIPS in Montreal. Jeff Dean, a senior fellow at Google AI, tweeted to the prime minister two weeks ago: “It seems pretty unlikely that a graduate student in machine learning studying in the U.S. (likely a member of [Black in AI]) won’t go back to the U.S. after attending [NeurIPS] for a week in Montreal in December. Anything you can do here?”

Last year, some three of about 60 Black in AI attendees were denied visas to the event in Long Beach, Calif., tweeted AI research scientist Timnit Gebru. For this year’s Montreal conference, around half of the attendees have been denied visas, said Gebru.

It’s not just Canadian conferences that pose visa problems for African attendees. Earlier this month, Element AI’s Bengio told MIT Technology Review that another major AI conference, the International Conference on Learning Representations, will be held in Africa next year partially due to the number of visa issues applicants face.

“In Europe or the U.S. or Canada, it is very difficult for an African researcher to get a visa,” said Bengio. “It’s a lottery, and very often they will use any excuse to refuse access. This is totally unfair.”