Prime Minister Scott Morrison says he wanted Bill Shorten to “look me in the eye and tell me the truth” when he appeared to invade the personal space of his rival during the second televised leaders’ debate.

Labor senator Kristina Keneally on Saturday claimed the awkward encounter revealed Mr Morrison was aggressive and desperate, labelling it his "Mark Latham moment" in reference to the former Labor leader's infamous 2004 handshake with John Howard.

Mr Shorten narrowly won the wide-ranging debate, according to the studio audience of 100 undecided voters. However it was Mr Morrison’s actions during a heated discussion on tax policy that provided the most memorable moment.

The pair were free to roam the stage during the contest. At one point Mr Morrison stood close to Mr Shorten while grilling him over Labor’s proposed tax increases for high-income earners.