Somalia has joined the East African Community (EAC) in a move intended to boost economic growth in the country following three decades of war.
President Hassan Sheikh Mohamud said joining the regional trade bloc was a "beacon of hope" for Somalia.
He said it offered "hope for a future of opportunities and prosperity".
Somalia has been wracked by conflict since 1991 and many parts of the country are controlled by jihadist group al-Shabab.
Some of its neighbours have sent troops to help fight the Islamist group, which is affiliated to al-Qaeda.
The decision to admit Somalia was made after a meeting of heads of member states in Arusha, Tanzania.
Somalia's integration into the EAC is a huge step for the Horn of Africa nation, but it did not come easy.
Months of lobbying to join the regional bloc were met by serious questions and hesitation by some member states.
EAC citizens can move freely within member states, so some fear that it could be easier for al-Shabab fighters to move around the region.
To be admitted into the EAC, new countries are supposed to show that they adhere to the principles of good governance, democracy, the rule of law, human rights and social justice.
Last year, Somalia was ranked the most corrupt country in the world by Transparency International.
So some argued that Somalia was not ready to join the bloc.
Negotiations between the EAC and Somalia began in August hosted by the Kenyan government.
President Hassan assured the EAC that his country was working tirelessly to address the issues, with the support of member states.
He went on a charm offensive, pointing to his country's 3,000km coastline which would link the region to the Arabian Peninsula, a vibrant economic zone and Somalia's marine economy like fishing.
This offer seems to have been too good for the EAC countries to turn down.
Friday's announcement has prompted mixed reactions.
Those in support said on X, formerly Twitter, that the admission was long overdue adding that the region will benefit significantly.
Others said more time should have been taken, arguing that the EAC might inherit some of Somalia's challenges.
The bloc is aiming to expand its market size as it hopes to integrate all countries in the Horn of Africa.
Earlier this year, EAC Secretary General Peter Mathuki hinted that Djibouti and Ethiopia would also join the bloc.
The Democratic Republic of Congo joined in March last year.
Somalia becomes the eighth member of the EAC after Burundi, DR Congo, Kenya, South Sudan, Tanzania, Rwanda and Uganda.
