'He pumps himself up by putting other people down': Obama blasts 'insecure' Trump

President Obama blasted Donald Trump hours before the second presidential debate on Sunday, labeling the Republican candidate 'insecure' and 'disturbing'.

He did not even acknowledge the businessman by name as he chipped away at his 'insulting' campaign at a fundraiser for Democratic representative Tammy Duckworth, in Chicago, Illinois. 

'It tells you that he's insecure enough that he pumps himself up by putting other people down,' Obama quipped, listing what he considered to be the candidate's most offensive moments to date.

'One of the most disturbing things about this election is just the unbelievable rhetoric coming from the top of the Republican ticket. 

'I don't need to repeat it. There are children in the room. 

'But, demeaning women, degrading women, but also minorities, immigrants, people of other faiths. Mocking the disabled. Insulting our troops. Insulting our veterans. 

'That tells you a couple of things,' he said to applause, NPR reported.