Historic changes to media ownership laws, which would open the door for a flurry of mergers and acquisitions, are closer than ever to being passed.

The government remains locked in talks with the Nick Xenophon Team, which holds three decisive votes. Senator Xenophon has said he wants to secure tax breaks for independent journalism and some kind of controls or levies on Facebook or Google in exchange for his party's support.

The legislation needs 38 votes to pass the Senate, where the Coalition controls 29 votes. It has already secured the support of three cross benchers and four Pauline Hanson's One Nation senators, but is remains two votes short.

The legislation has been on the Senate list for several weeks, but finally made it to debate on Tuesday around lunchtime, with 16 senators listed to speak. Six were able to speak before debate was interrupted for question time.