OSLO (Reuters) - The International Maritime Organisation aims to agree this week on steps to cut greenhouse gas emissions in the global shipping industry by making vessels more energy-efficient, officials said.

Norwegian ministers and IMO representatives said they hoped a meeting that opened in Oslo on Monday would reach agreement on design standards for new ships.

"My hope is that the foundation will be laid here in Oslo for an ambitious package of measures leading to real reductions in greenhouse gases from international shipping," Norway's Minister for the Environment and International Development Erik Solheim said in a statement.

Different studies estimate the share of world carbon dioxide emissions from international shipping at between two and four percent, comparable with that from the aviation industry.

But IMO Secretary-General Efthimios Mitropoulos told reporters the exact proportion was unclear and the organisation had decided to carry out new studies.

"That is why we have engaged scientists, to get up-to-date, concrete findings," he said.