Oil prices rose slightly in early Asian trade on Tuesday, a day after Saudi Arabia denied a media report that it was discussing an increase in oil supply with the Organisation of Petroleum Exporting Countries (Opec) and its allies. Brent crude futures rose 17 cents, or 0.2 per cent, to $87.62 by 0007 GMT. US West Texas Intermediate (WTI) crude futures for January began trading Tuesday, rising s