Some 400 US and Senegalese troops on Tuesday wound up an unprecedented joint training exercise aimed at preparing for a possible emergency deployment of American troops in Africa.

"Security issues, safety, any kind of emergency. The idea is to always be ready for an emergency response," US defense attache Colonel Scott H. Morgan told AFP at the training venue in Thies, east of the Senegalese capital, Dakar.

Around 200 troops from an infantry battalion based in Georgia and 200 Senegalese paratroopers took part in the two-week "Africa Readiness Training" exercise.

It is the latest sign of stepped-up military cooperation between the two countries.

A defence accord signed in May allows "the permanent presence" of American soldiers in the west African country, while making no mention of US bases in Senegal.

A key point of the deal was to give US troops access to areas in Senegal, such as airports and military installations, in order to respond to security or health needs.

It also allowed for joint training so as "to be better prepared to respond together to the risks which threaten our common interests."

"We have been sharing a lot," said Lieutenant-Colonel Souleyman Kande, who commands the Senegalese paratroopers.

"They are changing. They adapted their way of doing things to ours."

After Ebola, which caused more than 11,000 deaths between late 2013 and this year in West Africa, diplomats say a future crisis could be another epidemic, a natural disaster calling for a humanitarian response, "or a terrorist threat".

Senegal has been spared the deadly jihadist attacks that have hit neighbouring Burkina Faso, Mali and Ivory Coast, but has beefed up security in many public places.