Jeremy Corbyn said the government was financing oil and gas projects that produce 69m tons of carbon annually.
He said that was “nearly a sixth of the total emissions from this country alone” and the government would not meet its net zero emissions policy before 2099.
Boris Johnson said the government had “doubled” its spending on tackling climate change, and the UK has reduced its C02 emissions by 42% on 1990 levels.
Watch Politics Live in full for 30 days from transmission (UK only)