[1] On the one hand, the Catalan Centre started negotiations with the UCD Catalan branch and other political parties throughout the second half of 1977,[13] leading to the establishment of the Union of the Centre of Catalonia (UCC) in March 1978, with which the UCD would first sign an electoral agreement for the local elections,[2] then establish a common platform in June that year—often referred to as a "liaison political committee"—to oversee a future merger between both parties.

[1][3] This course of action was initially met with skepticism within several UCD sectors, with some remaining reluctant of negotiating under equal conditions with political groups failing to garner any electoral successes, and some others—such as Adolfo Suárez himself—being weary of consenting to a breakdown of the UCD's organic unity in order to create an autonomous party in Catalonia.

[1] On the other hand, the internal crisis within the Democratic Union of Catalonia resulting from its poor election results, coupled with its quest for a strong electoral ally, divided the party among those favouring a rapprochement to the CDC–EDC bloc and those advocating for a merger with the UCD to form a large Catalan-based centrist platform.

[1][14] Cañellas and the UDCA engaged in talks with the UCD–UCC platform, leading to the establishment of the "Centrists of Catalonia" alliance on 24 November 1978.

[15][16] The newly-formed alliance would contest the 1979 general and local elections—seeing a moderate success in the former and more discreet results in the latter[17][18]—with its ultimate goal being to negotiate the full merger of its constituent parties into the UCD to grant it "full Catalanist and democratic credibility",[10] as well as advancing towards their common goal of establishing a "broad centre" space.