EU lawmakers on Tuesday refused to endorse former Dutch foreign minister Wopke Hoekstra's candidacy for a top EU climate job, after criticism of his past ties to the oil industry.

The European Parliament's environment committee grilled the 48-year-old conservative politician Monday over his track record and perceived lack of experience on climate issues.

But he failed to get the backing of two-thirds of the legislators required to then head to a vote by the whole parliament.

The committee asked him to provide more answers, including details on the 11 years spent working for consultancy giant McKinsey, before lawmakers hold a new meeting on Wednesday morning.

The European Commission, the EU's executive arm, has proposed Hoekstra take on the climate portfolio after his compatriot Frans Timmermans returned to domestic Dutch politics.

Timmermans had been a powerful executive vice president on the commission, in charge of overseeing the ambitious climate pact known as the European Green Deal.

That job has passed to Slovakia's commissioner Maros Sefcovic and Brussels now wants Hoesktra to serve under him as the official in charge of "climate action".

The environment committee also refused to endorse Sefcovic for the position at a hearing.

Lawmakers asked him to provide more answers on his ties to pro-Russian populist politician Robert Fico, who is looking to form a government after winning elections at the weekend.

Pascal Canfin, the head of the environment committee said the question remained whether Sefcovic was committed "to defend the EU position on the energy embargo against Russia".

After graduating from university, Hoekstra worked for energy giant Shell for two years before moving on to McKinsey.

He was appointed as finance minister to serve in Dutch Prime Minister Mark Rutte's third coalition government in 2017 before becoming foreign minister in 2022.

If he gets approved by MEPs and EU country leaders, Hoekstra would serve in the climate role until at least May next year, when a new commission will be formed after the European Parliament elections.

Despite the short tenure, that would still see Hoekstra spearhead the EU's delegation at the upcoming COP 28 climate talks in the United Arab Emirates.

His nomination for the crucial position was criticised by climate action advocates owing to his past at Shell and track record in power.

Green groups pointed to his opposition to ending exploitation of a major gas field, his blocking of measures to reduce nitrogen emissions and propping up of airline KLM.

The reshuffle of key EU climate jobs comes as the bloc's green ambitions face a difficult moment.

There has been growing resistance from some EU member states, and some right-wing MEPs have called for a "pause" in environmental legislation.