Southern Libya has become a "viper's nest" for Islamist militants and the only way to tackle it is with a strong collective response from neighbouring countries, France's defence minister said in remarks published today.

"We are increasingly worried. It's a viper's nest in which jihadists are returning, acquiring weapons and recruiting," Jean-Yves Le Drian said in an transcript of an interview provided by the ministry. "It is dangerous and the conditions are not in place to find a solution."

Two-and-a-half years after the fall of former leader Muammar Gaddafi, the oil-rich North African state is struggling to contain violence between rival forces, with Islamist militants gaining an ever-stronger grip on the south of the country.

With no desire to get involved militarily, Western countries have pledged for months to train Libyan security forces so they can better protect borders, but with few actually doing so.

France had been due to begin training 1,000 Libyan police officers at the end of March, but that plan appears on hold.

"The only possible response is a strong collaboration between neighbouring states to ensure border security because there is no state in Libya," Le Drian said. "We are ready to train policemen, but there are no volunteers."

A French-led military offensive launched in Mali in January 2013 broke the grip of al Qaeda-linked militants over the north of the West African country, but small pockets of Islamists have re-grouped to operate the vast desert region of West and North Africa.

The five permanent members of the United Nations Security Council and regional countries met in Rome last month to try to find ways to tackle the crisis in Libya, but yielded few results and within days the country was plunged into more chaos when the prime minister was removed.