On November 18 and 19, 1999 in Strasbourg a Rainbow delegation participated in the proceedings of the General Assembly of the Greens/EFA parliamentary group. As of April 20, 1999 Rainbow has participated with an observer status in the EFA (European Free Alliance), a coalition of minority and regional parties from member countries of the EU. According to the EFA statute, after the period of one year with the status of observer, Rainbow will become a full member.

Ten members from the coalition were elected to the European Parliament in the last elections. The MPs are from those minority parties that succeeded in exceeding the 3% or 5% limits in the countries they come from. Two MPs were elected from Belgium (the Flemish Party), four from Great Britain (two from the Scottish Party and two from the Welsh Party) and four from Spain (one each from the Basque, Galician, Catalon and Andalusian Parties). In the General Assembly on November 18, 1999 the position of the lesser-used languages in France and Italy were discussed due to the fact that these countries have not signed the Charter of the Minority and Regional Languages of the Council of Europe. On November 19 there were discussions, among others, about the political agreement between the Greens and EFA and their decision to join forces and work together in the European Parliament under the common name GREENS/EFA. With this the new coalition becomes the fourth largest party in the European Parliament by the number of MPs: 38 from the Greens and 10 from the EFA.

During the proceedings of the General Assembly the Rainbow delegation had the opportunity to present, both verbally and in writing, the problem of the Macedonian language in Greece regarding the lack of recognition and respect of the collective rights of the Macedonian national minority by the Greek state. Within this framework ideas were exchanged regarding the intensification of the cooperation between Rainbow and the members of the Greens/EFA who participate in the work of the relevant commissions of the European Parliament (the Cultural and Education Commission and the Foreign Relations Commission). One of the ideas was a possible visit during 2000 by a delegation of the European Parliament to the villages and towns in Northern Greece where the Macedonian population lives.