Earlier this week, the EU approached Prime Minister Rishi Sunak’s government with proposals that could extend the phasing-in of tariffs on EVs traded between the bloc and the UK for at least two years, according to people familiar with the talks.

Under current arrangements in place after the UK’s withdrawal from the EU, electric vehicles traded between the two starting next year would be subject to a 10% tariff if less than 45% of their value comes from the region. European carmakers have warned those tariffs could cost the sector €4.3 billion ($4.5 billion) and benefit Chinese competitors.

One of the options under discussion is an arrangement that would effectively delay the imposition of tariffs by about two years, the people said.

Talks are ongoing and no final decision has yet been made, with the possibility that discussions drag on for longer, said the people.

Electric vehicles have become a major focal point of global trade tensions in recent weeks as Europe frets that its car manufacturers will lose out to Chinese manufacturers in the transition to less polluting cars. The EU this month launched an investigation of Beijing’s financial support for the EV industry.

The UK government and European carmakers have sought to extend the phase-in period for tariffs by three years, backed by many EU member states including Germany. That possibility remains on the table, according to the people. France has been opposing a delay.

The EU was moving away from its initial position that a delay was not acceptable, and months of work on the issue have started to bear fruit, a UK government official said, requesting anonymity to discuss private conversations.

Read more: China’s Clean Car Exports Surge as Europe Starts Subsidy Probe

European carmakers recently dialed up pressure on policymakers to delay the tariffs, saying they could reduce production in the region by 480,000 cars over three years. The European Automobile Manufacturers’ Association said it has not yet had “any formal communication” from the European Commission on possible alternative options to amend the so-called rules of origin in the post-Brexit trade agreement.

“While we appreciate that efforts are being made to prevent 10% tariffs being levied on electric vehicles in just a few months, we stand by our call for a simple, medium-term solution: extend the current phase-in period for battery rules by three years,” ACEA director general Sigrid de Vries said in an emailed statement on Friday.