The European Union announced on Thursday the start of an investigation into Chinese manufacturers of photovoltaic solar panels.
The action came a day after the US International Trade Commission determined that imports of Chinese photovoltaic cells and modules have hurt the US solar industry.
Analyst said the decisions will lead to a trade war in the global renewable energy market, which will impede the development of solar energy technology.
The EU's investigation into whether the Chinese government gives subsidies to solar panel manufacturers comes after a separate European inquiry looked into charges that Chinese companies were selling photovoltaic solar cells into the European market below cost, a practice known as dumping.
The anti-subsidies case involves 21 billion euros ($27 billion), making it the largest case of its type initiated by the European Commission, the European Union's executive body.
The commission started on Sept 6 to investigate whether Chinese manufacturers have dumped solar panels on the EU market.