OSLO, May 3 (Reuters) - Norway’s $1.3 trillion sovereign wealth fund, the world’s largest, will raise the bar on which companies will be included in its portfolio, the fund’s CEO said on Monday. “We will now be doing more screening in advance of small companies, before they are included in the portfolio,” fund CEO Nicolai Tangen said in prepared remarks to the Norwegian parliament’s finance committee. This screening will come in addition to the proposed plan by the government to reduce the number of companies in the fund’s global reference index, mostly by cutting the number of small companies. (Reporting by Gwladys Fouche, editing by Terje Solsvik) Our Standards: The Thomson Reuters Trust Principles.