BELGRADE (Reuters) - Nine countries in the Black Sea region and southeast Europe agreed on Thursday to reduce greenhouse gas emissions in large power plants and oil refineries by 2027 as part of plans to forge closer ties with the European Union.

Aging coal-fired plants dominate power generating capacities in Albania, Bosnia, Georgia, Kosovo, Montenegro, Macedonia, Moldavia, Serbia and Ukraine which are all striving to intensify energy market cooperation with the EU.

The nine countries, along with the EU, are members of the Energy Community which fosters energy market cooperation between the bloc and neighboring countries.

Serbian Energy Minister Zorana Mihajlovic said a reduction of sulfur, dust and nitrogen emissions from combustion systems in power plants and refineries had to be gradual and would begin in 2018.

"We cannot just shut down old (coal-fired) thermal plants, because that would leave the region without electricity," she said.

Since 1990, the region has only seen about 0.94 gigawatts (GW) of new utility scale plants put in place and to ensure adequate power supply, it needs to invest around 40 billion euros ($55.13 billion) until 2020.

Energy ministers from the countries, meeting in Belgrade, also agreed a list of 35 priority projects for which EU funding would be available.

"14 electricity generation, nine electricity infrastructure, ten gas infrastructure and two oil infrastructure projects were selected due to their importance for the development of cross-border energy markets in the region," The Energy Community Secretariat said in a statement.

(Reporting by Ivana Sekularac; editing by David Evans)