The week-long session will also review for the first time draft laws on social security and state assets.

The income tax law was last revised last year when the taxable income level was set at 1,600 yuan a month, up from 800 yuan.

'The adjustment aims to relieve the burden of medium- and low-income earners and is within the country's financial capacity,' Finance Minister Xie Xuren told the legislative session.

The increase would free 70 per cent of income earners from paying tax, up 20 per cent from the present cut-off point, Mr Xie said.

The adjustment would also mean an increase in households' disposable income, which in turn would help them to cope with decade-high inflation.

State coffers would see a reduction of 30 billion yuan with the revision, he said. Revenue was expected to top 5 trillion yuan this year, up more than 27 per cent on last year.

Lawmakers yesterday also began reviewing the draft law on social security, which aims to tighten control of public funds following a string of embezzlement scandals.

The draft law states that all social security funds, which cover pension, medical insurance, work injury insurance, unemployment insurance and maternity insurance, shall only be used for their specified purposes.

The management details of these funds, which amounted to more than 400 billion yuan this year, should be made public to boost transparency, the draft law states.

A draft law aimed at protecting state assets from being stolen or sold at low prices was also being reviewed for the first yesterday.

It suggests the central government set up a budget system to oversee all deals by the country's more than 120,000 state-owned enterprises (SOEs), whose assets amounted to 9.7 trillion yuan last year.

'The loss of state-owned assets has been rampant during the reforms, as some SOEs sold their assets at well below market prices, gave them out for free, or their managers illegally seized them for their own benefit,' Shi Guangsheng, vice-chairman of the NPC Financial and Economic Committee, said.

Meanwhile, the nation's first anti-drug law, aimed at combating drug-related crimes and reducing the number of abusers, is among a slew of legislation expected to be passed at this week's session.

Lawmakers will review a final draft of the bill with revisions that include raising the age limit for compulsory rehabilitation to 16 from 14.

Opium, heroin, marijuana, Ice, morphine and cocaine are listed as banned drugs in the draft.

A revised version also says drug-addicted pregnant women who breast-feed babies under a year old are not suitable for compulsory rehabilitation.

At present, drug dealing is considered a crime under more general criminal laws.

The mainland has about 940,000 registered drug addicts, of whom more than 740,000 are hooked on heroin, according to official data.

Three other draft laws, regarding road safety, labour dispute negotiations and technology advancement, were also expected to be approved before the session concludes on Saturday.