The Turkish Energy and Natural Resources Ministry this week said it would seek to resolve a dispute among parties involved in building a $20 billion nuclear power plant to be run by Russia’s state nuclear corporation Rosatom in Akkuyu on Turkey’s southern coast, the Turkish state-run Daily Sabah reported.

Akkuyu Nukleer, a Rosatom subsidiary that is building four reactors at the site on the Mediterranean, said on Saturday that it had a construction contract with TSM Energj to undertake the remaining construction work at the plant after terminating its agreement with Turkish firm IC Ictas, the paper reported.

For its part, IC Ictas challenged the move, calling it unlawful and vowing to launch a legal challenge. The firm accuses Rosatom of attempting to “reduce Turkish corporate presence” within the Akkuyu Nuclear Power Plant project, said the paper.

TSM, based in the Turkish port city of Mersin, is owned by three Russia-based companies, according to the Turkish trade registry.

“All works under current subcontracts will be transferred to TSM … Similar new contracts will be signed between TSM and subcontractors,” Akkuyu Nukleer said in a statement, without saying why the IC Ictas agreement had been terminated.

Akkuyu Nukleer added that the contract with TSM would ensure work was completed by previously agreed dates and that workers were paid on time, the Daily Sabah said.

IC Ictas suggested the switch could lead to construction delays, and said it would take Rosatom to arbitration in London as well as pursue legal action in Turkey, the company said in a statement to Bloomberg.

The Turkish government aims to start operating the first reactor before a general election next year, Reuters reported, with the remaining three reactors following by 2026, ultimately reaching a total 4,800 MW capacity.

Once completed, the plant will produce 10 percent of Turkey’s electricity.

President Tayyip Erdogan has previously suggested that Turkey could work with Russia on the construction of two further plants, Reuters said. He is set to hold talks with Russian President Vladimir Putin in the Russian Black Sea resort of Sochi on this week, reported the Daily Sabah.

Akkuyu represents a plant built under Rosatom’s  build-own-operate model. Under the long-term contract, Rosatom has agreed to provide the power plant’s design, construction, maintenance, operation and decommissioning.

Rosatom  holds a 99.2% stake in the $20 million project, representing the biggest investment in Turkey’s history implemented at a single site.