The Colombian authorities claim to have scored a run of successes against principals in the nation’s drug trade.

Yet recent figures show that the area of land used to produce coca is still rising. Colombia is the world’s largest cultivator and the main source for cocaine that reaches Europe.

The UN estimated that the area used for coca production increased by 27 per cent last year. About 99,000 hectares (245,000 acres) of coca bush, producing 600 tonnes of refined cocaine a year, are produced in the country, primarily by the Revolutionary Armed Forces of Colombia (Farc).

The group, and other paramilitary groups, work with criminal cartels to export the drugs, mainly to North America and Europe. International criminal enterprises buy large quantities of near-pure cocaine from cartels and transport it to the Caribbean coast. From there it is taken into the United States or across the Atlantic. The chief point of entry into Europe for cocaine is Spain, with cargoes being dropped into the sea off Galicia.

One of the latest trends detected by antidrug agencies is for “mother ships” to drop off their cargoes to smaller vessels off the coast of West Africa.

A portion of the enormous financial gains from the trade remain in Colombia, where Farc has been fighting a 40-year campaign to overthrow the Government. More than a quarter of global cocaine seizures, 181 tonnes, were made in Colombia last year and the security services claim that their successes are devastating Farc.

General Freddy Padilla de Leon, the commanding officer of Colombia’s armed forces, speaking from Puerto Asis, near the Ecuador border, said that this year the armed forces will clear by hand about 100,000 hectares of coca bush. Another 140,000 hectares will be sprayed.

A trial in Ireland last week demonstrated the gains that can be made from the trade. Irish police estimate that for an investment of £20 million, the gang behind the attempt to deliver a tonne of cocaine to a remote part of the Cork coast before moving it into Britain could have multiplied its value tenfold by the time it was sold on the streets. The random seizure – the largest in Ireland or Britain – reveals the large volume of cocaine that continues to leave Colombia for Europe.

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