Apparatus for fluid supply to the interior of a portion of a tubular body portion comprising: a first selectably extendible tubular body portion sealing element which comprises a first selectably inflatable balloon and is adapted to be located at a first location along a length of said tubular body portion, and a second selectably extendible tubular body portion sealing element which comprises a second selectably inflatable balloon and is adapted to be located at a second location along said length, said first selectably extendible tubular body portion sealing element and said second selectably extendible tubular body portion sealing element being adapted to define an intermediate region of said length of said tubular body portion therebetween; a controller (122,125) adapted for selectably sealing said first and second tubular body portion sealing elements to said tubular body portion; and fluid supply functionality adapted for supplying a fluid to said intermediate region; an endoscopy auxiliary assembly configured to be mounted onto an endoscope by means of a tubular sleeve fixed over a distal portion of the endoscope, the endoscopy auxiliary assembly comprising: the first selectably extendible tubular body portion sealing element with the first selectably inflatable balloon being located peripherally, a tube communicating with the interior of the first selectably inflatable balloon for inflation and deflation thereof, and at least one external tube extending alongside the endoscope; an endoscope tool which extends through the at least one external tube, the endoscope tool comprising: a guiding tube which includes a first lumen for inflation and deflation of the second selectably inflatable balloon via an aperture; and a tip portion located distally of the second selectably inflatable balloon, the tip portion being more flexible than the guiding tube. a first selectably extendible tubular body portion sealing element which comprises a first selectably inflatable balloon and is adapted to be located at a first location along a length of said tubular body portion, and a second selectably extendible tubular body portion sealing element which comprises a second selectably inflatable balloon and is adapted to be located at a second location along said length, said first selectably extendible tubular body portion sealing element and said second selectably extendible tubular body portion sealing element being adapted to define an intermediate region of said length of said tubular body portion therebetween; a controller (122,125) adapted for selectably sealing said first and second tubular body portion sealing elements to said tubular body portion; and fluid supply functionality adapted for supplying a fluid to said intermediate region; an endoscopy auxiliary assembly configured to be mounted onto an endoscope by means of a tubular sleeve fixed over a distal portion of the endoscope, the endoscopy auxiliary assembly comprising: the first selectably extendible tubular body portion sealing element with the first selectably inflatable balloon being located peripherally, a tube communicating with the interior of the first selectably inflatable balloon for inflation and deflation thereof, and at least one external tube extending alongside the endoscope; an endoscope tool which extends through the at least one external tube, the endoscope tool comprising: a guiding tube which includes a first lumen for inflation and deflation of the second selectably inflatable balloon via an aperture; and a tip portion located distally of the second selectably inflatable balloon, the tip portion being more flexible than the guiding tube.