Mon Jul 8, 2013 5:18am EDT
* Athens needs 8 bln euros but payment set to be drawn out
* EU/IMF lenders say "outlook remains uncertain" for Greece
* Last week's Portuguese upheaval is uncomfortable backdrop
By Robin Emmott and Martin Santa
BRUSSELS, July 8 (Reuters) - The euro zone must decide on Monday how to keep Greece on a lifeline but is divided over whether to delay aid payments ...