SYDNEY (Reuters/AFP) - Australian Prime Minister Tony Abbott said on Monday it was unclear if the siege at a Sydney cafe, where hostages are being held, was politically motivated.

"We don't yet know if this is politically motivated, although there are some indications that it might be," Abbott told reporters in Canberra.

"This is a very disturbing incident. I can understand the concerns and anxieties of the Australia people," Abbott said, without providing any information on the unfolding siege.