Papua New Guinea's Registrar of Political Parties and Candidates says a proposed new Organic Law would stem the flow of defections of MPs from opposition to government.
Alphonse Gelu has expressed concern at the latest spate of defections which has decimated the opposition to just two MPs in the 111-member parliament.
Cross-floor movement has been a feature of parliament since a 2010 Supreme Court ruling watered down restrictions on party-hopping in the Organic Law on the Integrity of Political Parties and Candidates.
Mr Gelu says this needs to be tightened up for the sake of a vibrant parliamentary democracy.
"We've proposed a new Organic Law which won't keep members to their parties but basically it will make it tougher for them to leave their parties. So if we have ten members of parliament that are sitting in the opposition, under the revised laws we'll make sure that those ten must stick with their party, because if they want to leave there are certain things that we've put in place in this new revised law."