WARSAW (Reuters) - Poland is set to veto on Friday the European Union's 2050 road-map laying out emission reduction goals beyond 2020 as well as another document detailing the bloc's stance on global climate deal negotiations, two government sources said on Wednesday.

Environment ministers of the 27-nation bloc are meeting in Brussels on Friday with the aim of approving the 2050 road map, which Warsaw has already vetoed once, and to move towards a joint stance on the global negotiations.

"Technically, it's bound to be two vetoes," a senior government source said on condition of anonymity.

"We cannot agree to anything that would directly or indirectly allow for higher emission reduction goals in the near future," another government source added.

Poland relies on coal for more than 90 percent of its electricity needs and has been a staunch opponent of the EU's climate policies since it joined the bloc in 2004.

(Reporting by Gabriela Baczynska; editing by Jason Neely)