A general view of the hemicycle where plenary sessions are taking place at the European Parliament in Brussels
A general view of the hemicycle at the European Parliament in Brussels, Belgium, February 24, 2016.

The EU's plan to label investments in gas and nuclear power plants as climate-friendly faces a final vote on Wednesday when European lawmakers decide whether to accept or reject proposals that have divided governments and investors.

The vote is the final hurdle in the European Union's long-delayed decision on whether to add the two energy sources to its "taxonomy", a rulebook determining which investments can be marketed in Europe as being sustainable.

Designed to guide private capital towards truly green projects, the rules aim to set a European standard for sustainable investment and stamp out greenwashing among the myriad so-called eco-friendly products on the market.

But the debate about investments that can be marketed as green has morphed into a broader political stand-off over which fuels Europe should invest in to fight climate change and replace Russian gas.

EU lawmakers will debate the gas and nuclear rules on Tuesday and vote on Wednesday in what officials expect to be a tight ballot. A majority of the European Parliament's 705 lawmakers must vote against the proposal to block it.

Green lawmaker Bas Eickhout said the EU proposal would create artificial incentives to invest in nuclear energy and gas, a fossil fuel, at the expense of the renewable energy needed to rapidly curb planet-warming emissions.

European People's Party lawmaker Christian Ehler said the taxonomy's impact on future investment was not yet clear, but he said its harsh limits on CO2 emissions and other criteria would ensure investments in gas plants complied with climate goals.

Rejection would be a blow to the European Commission, which has spent more than a year redrafting the rules amid intense lobbying from governments and the gas and nuclear industries.

Brussels says gas and nuclear power plants must meet strict conditions to earn a green label.

Critics, including the Commission's advisers, have said gas plants would need to meet far tougher emissions limits than those in the Commission proposal to align with the steep cuts needed to avert severe climate change.

The Commission had included a lower emissions limit in an early proposal in 2020 but amended it after backlash from some of the bloc's 27 member states.

EU climate policy chief Frans Timmermans said on Monday that he would have decided differently on the taxonomy were it his choice alone, but that the rules reflected the political realities within the bloc.

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