Resident workers shall be given preference in employment in the Virgin Islands in any industry or occupation for which such workers are qualified and available. Nonresident workers shall be employed only to supplement the labor force of available and qualified resident workers. No resident worker shall suffer any reduction in his workweek below 40 hours a week by reason of an employer employing a nonresident worker. No employer shall employ a nonresident worker except in strict accordance with the provisions of this chapter and regulations issued hereunder. Nothing contained herein shall be construed to interfere with the policy of the Employment Service in the canvassing of affiliated state employment services to obtain workers before issuing clearance certification for alien workers.