The Micronesian country's shock withdrawal in July last year rocked the foundations of Pacific regionalism and raised questions about the power dynamics and politics within the Pacific Islands Forum.
In a statement on Monday, the Kiribati government confirmed the nation would be returning to the fold.
"The decision comes following a fruitful, positive, and successful bilateral meeting held between the current Chair of the Pacific Islands Forum and the newly elected Prime Minister of Fiji, Sitiveni Rabuka, and the President of Kiribati, Taneti Maamau, during the Prime Minister's State Visit to Kiribati earlier this year," the statement said.
"The meeting focused on strengthening bilateral relations between Fiji and Kiribati and discussed the restoration of unity in the Blue Pacific family as well as reaffirming the need to collectively work in unity and promote regional co-operation as enshrined in the 2050 Strategy for the Blue Pacific Continent."
But a senior lecturer at Massey University's centre for defence and security studies in New Zealand, Anna Powles, said this is only the first step towards restoring regionalism.
"A number of the decisions that need to be made under the Suva Agreement need to be made among the Micronesian countries themselves," she explained.
"For instance, where the sub-regional office is going to be located. Initially it was signalled that it would be in the Marshall Islands however, there are indications that Kiribati may be seeking to locate it there."
Pacific Islands Forum leaders are due to hold an extraordinary meeting in Fiji in March ahead of the official summit to be hosted in Rarotonga by the Cook Islands.
Speaking to the Islands Business magazine earlier this week, Fiji's Prime Minister Sitiveni Rabuka hinted at the likelihood of Micronesian leaders gathering prior to the March meeting.
"Hopefully we'll get the Micronesian bloc talking among themselves about the other things that they had asked for, asked the Forum Chair to consider, that will have to be taken back to them," Rabuka said.
Apart from its internal issues, the Pacific Islands Forum also has the added external pressure of heightened geopolitics in the region.
Anna Powles noted the absence of an official space for the Forum's so-called dialogue partners such as the US and China at last year's leaders summit. In fact the United States vice president Kamala Harris was the only one allowed to address Pacific leaders - a departure from the custom at past Forum summits.
"There are still questions around when it (dialogue partners' meeting) will be held this year. So there's a lot of sort of jostling amongst those external dialogue partners for position in order to engage with the Forum," said Dr Powles.
"So I think what we'll see this year is a sort of a continuing kind of shake down of regionalism."
Dr Powles added that at a sub-regional level bodies like the Melanesian Spearhead Group and the Polynesian Leaders Group will have a really important role to play as the Pacific Islands Forum goes through the process of implementing its 2050 strategy for the blue Pacific continent.