In the June 2007 parliamentary election, Ngouolali stood again as a candidate for the sixth constituency of Talangaï, but he was defeated.[4] He subsequently left the UFD in October 2007, objecting to the party's decision to join the Presidential Majority supporting President Denis Sassou Nguesso; according to Ngouolali, that decision was made by the leadership without properly consulting the rest of the party.[1] He then formed a new political party, the Action for the Rebirth of Congo (ARC), which he officially launched on 12 January 2008. The ARC initially drew most of its support from the Talangaï section of Brazzaville.[4] It joined an opposition coalition, the Alliance for a New Republic (ANR), in November 2008.[10]
In February 2009, together with 17 other opposition leaders, Ngouolali signed an agreement on the creation of a front intended to defeat President Sassou Nguesso in the July 2009 presidential election.[11] Ngouolali was one of 17 individuals who applied to stand as candidates in that election. However, in a ruling on 18 June 2009, the Constitutional Court rejected Ngouolali's candidacy on the grounds that he had provided a post office box number instead of identifying a place of residence. According to the Court, Ngouolali had thus failed to prove his continuous residency in Congo-Brazzaville over the preceding two years, as required by the Constitution. Ngouolali was one of four candidates whose applications were rejected by the Court.[12]
Speaking on 23 June 2009, Ngouolali complained that he did not understand why his candidate application was rejected, noting that he had documentation demonstrating his residency in Brazzaville. According to Ngouolali, an official had told him that, because he lived in an apartment, it would be acceptable for him to list a post office box instead of a street address. Nevertheless, Ngouolali stressed that he respected the Court's decision; his reluctance to criticize the Court stood in contrast to statements from some other opposition leaders, who did not hesitate to denounce the Court's rulings as politically motivated. He expressed his hope that "one day, when the sun of freedom, genuine democracy, national unity, and reconciliation truly shine on Congo", he could participate in a "genuine opposition".[13]
Marking the ARC's second anniversary at festivities in Brazzaville on 19 February 2010, Ngouolali said that the elections held under Sassou Nguesso were not genuinely democratic, and he called on his party to work for a return to the kind of democratic elections that were held in the 1990s. He argued that the ARC's strength was not reflected in the official results of the 2008 local elections.[14]
The ARC was included in an opposition coalition, the Front of Congolese Opposition Parties (FPOC), and at FPOC's third national convention, held in Brazzaville on 9–10 April 2011, Ngouolali was elected as President of FPOC. He succeeded Clément Mierassa at the head of the coalition; its leadership was held on a rotating basis.[15]