Ukraine and Russia take centre stage as leaders gather for G20

Police guard cleared streets near the venue of the annual G20 leaders summit in Brisbane November 14, 2014. REUTERS/Jason Reed

BRISBANE Australia (Reuters) - A showdown between Western leaders and Russian President Vladimir Putin is likely at the G20 summit in Australia starting on Saturday, following fresh reports of Russian troops pouring into eastern Ukraine.

Ukraine has accused Russia of sending soldiers and weapons to help separatist rebels in eastern Ukraine launch a new offensive in a conflict that has killed more than 4,000 people.