EU activists put pressure on Brussels to withdraw climate and energy brief from Spanish minister with links to oil industry

Miguel Arias Canete has been dubbed 'Señor Petrolhead'

The appearance of Miguel Arias Canete at a Brussels hearing last Wednesday caused 100,000 people to sign a petition to prevent his appointment (EPA)

The recently nominated Spanish EU Commissioner for Climate and Energy has acquired an unwelcome title – "Mr Petrolhead".

This week, Miguel Arias Canete's links to the oil industry have left him under increasing pressure to stand down. An online petition calling on Brussels not to confirm Mr Canete's role has reached nearly 460,000 signatories. Almost 100,000 have been added since last Wednesday, when the former Spanish minister for the environment and agriculture was grilled at a confirmation hearing in Brussels.

The hearing focused on the 64-year-old's alleged family and financial links to two petrol companies. Mr Canete has only recently sold sizeable portfolios of shares in two Spanish oil firms, Petrolifera Ducar, of which he is a former president, and Petrologis Canarias.

Miguel Domecq Solis, his brother-in-law, remains a director of both companies, and his son was a board member. According to the newspaper El País, five questions about Mr Domecq Solis's role in the two businesses went unanswered by Mr Canete, who described them as "very small companies, only storing fuel".

Although measured and cautious in his answers to the deputies, Mr Canete has been considered a loose cannon. He once tried to lift his ecological credentials by boasting that he took cold showers to save on water heating, but then his love of collecting classic cars and rally driving led one auto magazine to describe him as "almost more a car fan than a minister". He also justified a government move to change lactose product regulations in 2012 by claiming he often ate yoghurts "five days past their sell-by date".

Arguably his most high-profile blunder came this spring when he insisted that he held back in debates with female opponents because he did not wish to abuse his intellectual superiority – something for which he apologised on Wednesday.

Now 76 EU deputies have signed a petition requesting his nomination be suspended. "Giving Arias Canete this job would be as dangerous as putting a kleptomaniac in charge of stock-taking in a Poundland shop," said Javier Couso, a Spanish deputy in the left-wing Izquierda Unida coalition. "There could not be a less suitable person," added Alejandro Gonzalez of Spain's Amigos de la Tierra [Friends of the Earth].

Environmentalists in Spain say that during his spell at the Ministry of Agriculture Mr Canete failed to oppose cuts to renewable energy subsidies, in a country once considered a world leader in the sector; laws designed to boost fracking; and a review of the closure of one of Spain's oldest nuclear power plants.