The Australian Greens are reserving the right to vote against the federal government's controversial media reforms this week, according to communications spokesman Scott Ludlam, who says his party in unhappy about having a gun held to its head.

Communications Minister Stephen Conroy wants his package of six bills passed by both houses of parliament by Thursday, but had announced that will not be open for "barter" - a move that has angered independents and the Greens.

The government needs four of the six remaining crossbenchers, including lower house Greens MP Adam Bandt, to support the bill, after former Labor MP Craig Thomson declared he would vote against it.

So far, while issues have been raised, none of the other crossbenchers - Rob Oakeshott, Bob Katter, Peter Slipper and Andrew Wilkie - have stated their final opinions.

On Saturday, Senator Ludlam said he was yet to reach a firm position on the package - given there are two inquiries into the reforms set for early this week - but said he had serious concerns about three elements of the reforms.