Qatar and Chad restore relations amid Gulf crisis
Lolwah al-Khater, the Foreign Ministry spokeswoman, posted on Twitter that both countries would return their ambassadors with immediate effect.
"Moments ago MOU (memorandum of understanding) was signed between Qatar and Chad; Diplomatic relations to be resumed with immediate exchange of ambassadors," she tweeted.
The agreement was "a victory for both countries", added Khater.
Qatar's foreign minister accused the Chadian government of accepting a bribe from the UAE to turn against Doha despite years of close relations.
"Why did Chad, shortly after it declared support for the bloc, obtain a reconstruction conference in the UAE?" Sheikh Mohammed bin Abdulrahman al-Thani asked last October.
Al-Thani has since praised the move to restore diplomatic ties, tweeting: "We welcome the resumption of diplomatic relations between Qatar and Chad and the return of ambassadors between the two friendly countries. A memorandum of understanding on this matter was signed today in Doha."
Saudi Arabia, Egypt, Bahrain and the United Arab Emirates cut ties with Qatar in June, accusing Qatar of backing extremism and fostering ties with Iran - charges that Doha denies.
A dozen other African and Asian countries, heavily dependent on financial aid from the Saudi-led bloc, followed suit, either downgrading or completely cutting ties with Qatar.
Qatar retaliated by closing Chad's embassy in late August and ordering all staff to leave the country.