The haze has caused pollution levels across the Southeast Asia region to spike to unhealthy levels

By Bernadette Christina and Michael Taylor

JAKARTA, Oct 30 (Reuters) - Indonesia is reviewing laws that allow farmers to burn up to two hectares (five acres), forestry officials said, the latest in so-far unsuccessful efforts to halt fires that have sent choking smoke across much of Southeast Asia.

Indonesia is also considering declaring a national emergency over the fires, which this week caused President Joko Widodo to cut short an official trip to the United States and pushed the country's greenhouse gas emissions above the daily average from all economic activity in the U.S.

A 2009 law allows smallholder farmers to use slash-and-burn practices to clear land for agricultural purposes, and has been cited by green groups and plantation firms as a key cause of the annual fires when the burning gets out of control.

"The problem is that some people take advantage of this exception," Indonesia's environment and forestry minister, Siti Nurbaya Bakar, told reporters when asked about the law.

"In our last cabinet meeting, the president assigned us to review a regulation that allows land burning for two hectares."

Revising the law may need parliamentary support which could delay changes until 2016, said Bakar, adding that the government was therefore considering an emergency regulation.

Forestry experts say the best way to clear forested areas is by tractors, chainsaws or hand tools. These methods are more expensive and time-consuming than fires.

The haze has caused pollution levels across the region to spike to unhealthy levels, and forced school closures and flight cancellations.

Warships are on standby to evacuate infants and other vulnerable residents of haze-hit areas, while other countries have been asked for help to tackle the fires.

The fires, often deliberately set by plantation companies and smallholders, have been burning for weeks in the forests and carbon-rich peat lands of Sumatra and Kalimantan islands.

"We support our government's initiative to revise the provisional laws that allow small-holder farmers to clear up to two hectares of forested land by burning," said Aida Greenbury, managing director of sustainability at Asia Pulp and Paper (APP). "But a multi-stakeholder initiative to support the local farmer and community must be initiated in parallel.

"The key here is to assist the farmers and the community in developing their land responsibly without burning."

Indonesia usually enters its wet season in October and November, and despite the El Nino dry conditions, rain has been reported in parts of Sumatra and Kalimantan this week.

(Reporting by Bernadette Christina and Michael Taylor; writing by Michael Taylor; Editing by Nick Macfie)

Our Standards: The Thomson Reuters Trust Principles.