Guinea, Sierra Leone and Liberia, the three states hardest hit by an epidemic of Ebola, have said they had set a target of reducing the number of new cases to zero within 60 days.

The worst Ebola epidemic in history broke out in late 2013 in Guinea and has killed more than 9,000 people in all. Its spread is slowing but the World Heath Organization (WHO) warned of complacency after a recent spike in cases.

"The heads of state and the governments of the Mano River Union recognise the effort deployed by the states and the international community which has led to a decline in Ebola. They want to achieve zero new Ebola cases in 60 days from 15th Feb. 2015," Guinea's presidency said in a statement.

However, the number of new Ebola cases increased for the second consecutive week, with 144 new confirmed cases reported in the week to Feb. 8, the WHO said on its website.

Guinea reported 65 new confirmed cases, compared with 39 the week before. Sierra Leone had 76 new confirmed cases while Liberia continues to report a low number of new confirmed cases.

Guinean President Alpha Conde has announced a national plan to have no Ebola cases by early March.