Colombia's government and representatives of the Farc guerilla movement closed another round of peace talks on Thursday without reaching a deal on agrarian reform, the first of six agenda points for negotiations in Havana.
Expectations had been high that an initial agreement was imminent on land issues, which were the root cause of Colombia's five-decade armed conflict.
"There can be no turning back. We continue to forge ahead always, advancing slowly if one wants to think so, but also persistently," said Farc commander Ivan Marquez.
Foreign Minister Alistair Burt's admission that the Cameron government has "supported" a survey of attitudes to US drone strikes in Pakistan's tribal areas amounts to a tacit admission of British involvement.