MIDEAST STOCKS-Blue chips lift Saudi; Egypt extends sell-off

(Updates with Saudi Arabia, Egypt open) DUBAI, May 14 (Reuters) - Saudi Arabia's stock market rose in early trade on Thursday on the back of blue-chip names, while a broad sell-off on Egypt's bourse continued following the reduction of the country's weighting in MSCI's emerging markets index. The main Saudi index edged up 0.7 percent as lenders Al Rajhi Bank and National Commercial Bank jumped 2.4 and 2.2 percent respectively. Petrochemicals giant Saudi Basic Industries surged 2.7 percent even a