MONTREAL, Canada -- The Canadian environment minister was traveling Saturday to Beijing for talks on climate change and biodiversity, the first visit there by a Canadian minister in four years.

Steve Guilbeault will take part in three days of talks starting Monday at the annual assembly of the China Council for International Cooperation on Environment and Development (CCICED).

"Climate change and environmental issues know no borders," he said in a statement. "We cannot tackle these existential threats without engaging with a wide range of stakeholders and partners."

Coming after years of strained bilateral ties -- made worse by Canada's 2018 arrest, at US request, of a Chinese telecoms executive -- Guilbeault's visit has been blasted as "treason" by some in the Conservative opposition.

In comments to Radio-Canada, Guilbeault defended his trip, saying it was crucial that his country broaden collaboration over the climate and biodiversity while also trying to repair diplomatic ties with China, a major trade partner.

He said he had developed a relationship with Chinese counterpart Huang Runqiu that allowed the two to "sit at a table despite our differences and talk about difficult subjects."

The two countries put aside their tensions last December while serving as co-organizers of the COP15 biodiversity conference in Montreal, which produced a historic agreement.

But tensions have lingered since the 2018 arrest, at US behest, of Meng Wanzhou, chief financial officer of Chinese telecoms giant Huawei.

Only days after her arrest, two Canadians -- businessman Michael Spavor and former diplomat Michael Kovrig -- were arrested in China on what Canada said were trumped-up charges intended as retaliation for Meng's detention.

All three have since been freed, but tensions have persisted. Beijing complains that Ottawa has aligned its China policy too closely with Washington's aggressive approach, while Canadian authorities accuse China of interfering in its internal affairs.

Suggestions in recent months that members of China's diaspora had meddled in the last two federal elections in Canada, targeting critics of Beijing, have placed the government of Prime Minister Justin Trudeau under pressure.

China has denied the allegations.