The US Senate has frozen the transfer of millions of dollars in funds to the Colombian military pending investigations into concerns over human rights abuses and alleged ties between the country’s armed forces and paramilitary groups.

The decision to suspend 25 per cent of US military aid, worth $55.2m (€40.6m, £27.5m), was adopted by Democratic Senator Patrick Leahy, chairman of the Senate appropriations committee’s subcommittee on state and foreign operations, who is an outspoken critic of the level of military aid being sent to Colombia.