China has been approving the construction of new nuclear power plants with official statements referring to the reduction of greenhouse gas emissions associated with nuclear energy. The statements don't seem to mention the terms green nor do they draw a direct parallel to more conventional forms of renewable energy (like the wind/solar/hydro in your question).
Despite the lack of labels, I think it's worth mentioning because for all intents and purposes China uses nuclear energy to meet its greenhouse gas emission reduction targets.
Reporting by the South China Morning Post quoted a Chinese Cabinet statement following the approval of two nuclear plants in 2020, writing:
“Pushing forward the construction of nuclear power projects actively and steadily is an important measure to expand effective investment, enhance energy support and reduce greenhouse gas emissions,” the cabinet said in an official statement after the meeting.
The quote does mention the term investment but not in the context of how the Chinese government labels nuclear energy explicitly. The way I read the statement, it's more of an implicit approval of these kinds of projects that encourages investments.
(The reasoning on nuclear energy cost and taxes below may be a bit dated, it's the most recent information that I could find and understand given the language barrier.)
From a tax perspective, nuclear energy in China seems to share some of the benefits of renewable energy sources by being taxed less. According to a 2017 paper in Sustainability entitled Dynamic Integrated Resource Strategic Planning Model: A Case Study of China’s Power Sector Planning into 2050 by Yan Xu et al.:
From Table 4, Path 1 is based on the original assumption of S2, namely the high level of coal resource tax, environmental pollution tax, carbon tax and solar PV tariff subsidies, among this, the carbon tax will be levied from 2020. Thus, the LCOE [Levelised Cost of Energy] of coal power will rise quickly since 2020. Benefiting from the tariff subsidies policy, the generation costs of PV power show the tendency of rapid decline. Due to the lower generation cost, the hydropower and nuclear power will be selected and included in the planning preferentially. Because of a high level of coal resource tax, environmental pollution tax and carbon tax, the fuel costs of coal power would significantly increase, considering that the external cost to lead the LCOE of coal power would rise quickly and play a certain inhibitory effect of large-scale installation of coal power.
In other words, nuclear energy gets taxed more favorably compared to fossil fuels like coal. That's not because the government labelled it a green option explicitly. Instead, the fundamentals of nuclear energy greatly reduce or exempt it from the coal resource tax and the carbon tax.
The paper also mention an environmental pollution tax but it's not clear to me if at the what extent that applies to nuclear energy. For example, spent nuclear fuel may need to be handled with care though it's not clear if China taxes that explicitly. I found a paper on taxes on spent nuclear fuel but it touches only briefly on China and it's not clear what the current policy is.
As for energy prices, it seems the Chinese set the rate at which energy producers may sell energy. At least in the past, nuclear plants were allowed to sell at higher prices compared to thermal (e.g. coal-fired) energy plants. According to a 2013 blog on piie.com:
Second, nuclear power producers benefit from more favorable pricing. In China, the National Development and Reform Commission (NDRC) controls the price at which power producers may sell their electricity to the grid. In order to promote the growth of cleaner forms of electricity (and save dwindling water resources) the rate thermal and hydro power producers receive for their electricity is set lower than nuclear, wind, and now solar power. Since 2007 the on-grid tariff for nuclear power has been between 10 and 25 percent higher than thermal power. This year, NDRC increased this gap further by lowering the on-grid tariff for thermal power, while keeping the tariff for nuclear power essentially stable.
In that article, they listed the average RMB prices per kWh for 2007 till 2010. They were (in descending order): 0.57 for wind, 0.44 for nuclear, 0.37 for thermal (e.g. coal), and 0.26 for hydro energy. That shows nuclear energy was allowed to charge almost 19% more than energy from thermal plants.
As I said, I'm not sure what this gap between nuclear and coal-fired prices looks like now. It seems the National Energy Administration (or rather their local counterparts) still issue these 'benchmark prices' based on this announcement for 2021 (in Chinese). In 2013 they released this announcement on nuclear energy specifically.
In conclusion, the lack of an explicit labeling of nuclear energy as green does not mean it's not considered green in practice. The Chinese government's communication and their energy pricing put nuclear energy on par with more traditionally renewable forms of energy.