By THE ASSOCIATED PRESS

              BOGOTA, Colombia (AP) -- Colombia's top rebel chieftain accused the
              United States on Monday of meddling with his country's internal affairs by
              sending ``hundreds of military advisers and mercenaries.''

              Manuel Marulanda, head of the Revolutionary Armed Forces of Colombia,
              or FARC, also warned that peace talks with the government will collapse if
              President Andres Pastrana forces the FARC to give up a Switzerland-sized
              safe haven he ceded to the rebels in southern Colombia.

              Marulanda, in a letter posted on the FARC's Internet site, said the peace
              talks ``will be over and not even the next president will have an open door''
              should Pastrana send his troops into the 16,200-square-mile zone he granted
              the rebels in an effort to boost the peace process.

              The United States is pumping $1.3 billion in mostly military counternarcotics
              aid to Colombia. But the rebels, who make huge profits in protection
              payments from cocaine producers in Colombia, see the U.S. assistance as a
              counterinsurgency campaign.

              Up to 800 U.S. military personnel and civilians contracted by the State
              Department are allowed in Colombia at one time under restrictions imposed
              by Congress. Green Berets have been training Colombian anti-drug troops
              and U.S. contractors piloting planes that fumigate drug crops.

              Negotiations with the FARC inside the so-called demilitarized zone have
              yielded little. Meanwhile, Colombia's military and U.S. officials have accused
              the guerrillas of using the area for military preparations, to stash hostages and
              to further enrich themselves in the cocaine trade.

              The Colombian army also said Monday that more suspected members of the
              Irish Republican Army visited the zone than previously believed. Three
              suspected IRA members were arrested last month after allegedly conducting
              explosives training for the FARC inside the zone.

              But two other suspected IRA members -- identified as John Francis Johnson
              and James Edward Walker -- traveled into the zone in April and left
              Colombia before they could be detained, an army spokesman said.

              Pastrana must decide whether to renew safe-haven status for the rebel
              territory, which is set to expire Oct. 6. He has indicated he probably will do
              so.

              Leading candidates in next May's presidential elections are calling for
              controls on the safe haven if not its outright cancellation should peace talks
              continue to founder.

              Front-runner Horacio Serpa is planning a protest caravan from Bogota to the
              area later this month. Last week, the rebels warned that the FARC cannot
              ``be held responsible for his security'' during the march.

              Colombia's 37-year conflict kills some 3,000 people annually.