A system and method is disclosed for the provision of assisted breathing by the delivery of a controlled pressurized airflow to the pulmonary airway of a user with breathing disorders. The system comprises a source of compressed respiratory gas, a user nasal interface unit including at least one Venturi device and a thin flexible tubing connecting between the source of high pressure gas and the Venturi device. The system and method provide a regulated and controlled flow of air to the user in accordance with the user needs. The invention further discloses a novel small light-weight nasal user interface for replacing prior art breathing masks.