Argentina's lower chamber of deputies gave overall approval to libertarian President Javier Milei's sweeping "omnibus" reform bill in a vote on Friday after days of debate, paving the way for a decisive vote in the Senate.

The controversial reform package was approved on a vote of 144 votes in favor, and 109 against.

The reforms that make up the bill include the privatisation of state entities, measures to enable reductions in generous state subsidies as well as the extension of some executive powers.

Lower-house lawmakers will also vote on the legislation article by article, which is expected to begin on February 6, but the general approval means it will now likely proceed to the upper house in some form.

Over the past few days, flag-waving protesters opposed to Milei's reforms have clashed repeatedly with riot police deployed outside the green-domed neoclassical congressional building, at times hurling rocks at them.

"I came to see how they are selling our country," said protester Liliana Lopez.

The mammoth bill is a key plank of Milei's reforms plans for Argentina's embattled economy, which is grappling with inflation above 200 percent, depleted foreign currency reserves and a time-bomb of debt repayments owned to creditors and investors.

Passing its initial hurdle in the lower house of Congress, the legislation marks the president's first major test since taking office in December after a shock election win for the economist who made his name as an acid-tongued TV pundit and campaigned with a chainsaw pledging to slash the size of the state.

The vote followed a long and heated debate in the lower chamber, with deputies for the main centre-left Peronist opposition bloc, Union por la Patria, voicing fierce rejection of Milei's policies while supporters urged them not to obstruct the bill.

Milei's La Libertad Avanza party only holds a small number of seats in the 257-seat chamber, but was still able to muster enough support from likeminded allies including from the main centre-right Juntos por el Cambio coalition of parties to advance the bill. (Reuters)