Nicolas Martin Cinto, the Spanish ambassador to Kenya, said: "We are happy the two are released."

"We paid no ransom for their release."

Somali kidnappers generally do not harm their victims, instead treating them as an investment which can pay off in the form of ransom.

The Spanish branch of MSF withdrew its workers from southern Somalia on Tuesday after the abductions in Puntland, which had enjoyed a reputation for relative stability compared to the rest of the anarchic Horn of Africa nation.