Democratic Republic of Congo said on Tuesday it had invited in Rwandan forces onto Congolese soil as "observers" for an offensive against Rwandan Hutu rebels which would last 10-15 days. "The operations are beginning. We have invited Rwandan officers with their security contingents for their safety. They are observers ... The operations to disarm the FDLR are planned to last 10 to 15 days," Lambert Mende, Congo's information minister and government spokesman, told Reuters.