KUALA LUMPUR :Malaysia's state energy firm Petronas plans to raise the share of its international portfolio to 60 per cent of its total business over the next decade, it said on Monday. The firm will build on its current international portfolio, which now accounts for around 40 per cent to 50 per cent of its investments, by integrating its domestic expertise with global partnerships, it said in a fact sheet shared with Reuters. In a volatile market, Petronas is upgrading its upstream operation