Gambia's new government has told the United Nations it will remain in the International Criminal Court (ICC), state media reported on Monday.
Earlier this month, the European Union pledged €225m ($240m; £191m) in aid to The Gambia as part of its effort to become a "privileged partner of The New Gambia". "This action is in line with our vision of a new democratic Gambia", the government statement said.
South Africa and Burundi also signalled past year they would quit the ICC and African Union member states earlier this month endorsed an unspecified "strategy of collective withdrawal".
Jammeh came to power in a coup in 1994 and his government established a reputation for torturing and killing opponents.More news: Drake Front-Runner For Grammy Album Of The Year
The police also opened a complaint register so that additional people could file reports.
Mr Jammeh, who ruled Gambia for more than two decades, initially refused to accept his election defeat, but after pressure from Senegal fled into exile in Equatorial Guinea.
British Foreign Secretary Boris Johnson, who notoriously sparked fury over comments about Africans made when he worked as a journalist, will visit the continent for the first time as minister this week.
It said the visit to The Gambia would be the first recorded visit by a UK Foreign Secretary.More news: Eight killed in Kashmir gunfight, protestors clash with security
"The Gambia will never be a member of any neo-colonial institution and will never be a party to any institution that represents an extension of colonialism", Mr Jammeh said at the time.
Barrow had promised a return to the 52-nation grouping.
"I am also very pleased that Gambia wants to rejoin the Commonwealth and we will ensure this happens in the coming months", Johnson said.
Mr Johnson will claim that Britain is "growing in influence and activity around the world" as he seeks to bolster relations with countries outside the EU.More news: Court Rejects Trump Travel Ban
Johnson is to meet President Adama Barrow and visit the British-funded Medical Research Council, his ministry said, resetting ties after years of tension with Jammeh.