Environment and Sustainability Minister John Griffiths warned that Japanese knotweed is an "expansive problem in Wales" on 21 November 2012.
The areas worst affected are Swansea and south Wales but it is spreading, he told AMs.
Liberal Democrat AM Peter Black raised concerns over the presence of the weed on private land as it can cause damage to concrete foundations, buildings and flood defences.
Labour AM Mike Hedges and Plaid Cymru AM Jocelyn Davies AM both highlighted the worries of people trying to sell houses who are plagued with the weed.
Whilst admitting that it was indeed "a difficult problem", the minister assured AMs that projects were under way to address the issue.
"One possible way forward is an insect which can offer a way of lessening if not eradicating Japanese knotweed", explained Mr Griffiths.
He also answered questions on energy prices, the new natural resources body for Wales and flood risk assessments.
Read this in Welsh.