Argentina has offered $6.5bn to settle a battle with creditors suing the country over defaulted bonds, seeking to end a long-running row that has hampered the country's access to international capital.

Friday's offer was made after talks in New York with hedge funds and other creditors who had previously demanded full repayment of about $9bn worth of bonds the country defaulted on 15 years ago.

Two out of six major holdout creditors have already accepted the deal, which includes about a 25 percent "haircut" on their claims, while four have not done so yet, according to the government.

Daniel Pollack, the US court-appointed mediator, hailed Argentina's proposal as an "historic breakthrough".

He said that if the offer is accepted and all the conditions are met, Argentina will be able "to return to the global financial markets to raise much-needed capital".

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The latest twist in a fight stemming from Argentina's record default on around $100bn in 2002 came less than two months after President Mauricio Macri took office and expressed his commitment to a deal.

If Macri manages to clinch an agreement, Argentina will be able to emerge from default and return to global capital markets to finance badly-needed infrastructure projects such as new roads and railways.

"The agreement was awesome," Argentina's finance minister, Luis Caputo, told reporters in New York. "We have had a good reception of the proposals and I feel optimistic."

"This is a big step in the right direction but this is not the end of it. Until the main holdouts accept a deal it is not over," Diego Ferro, co-chief investment officer at Greylock Capital Management in New York, told the Reuters news agency.

'Vulture funds'

On Wednesday, the Argentinian government agreed to pay Italian bondholders $1.35bn to settle $2.5bn in claims dating back to the default.

Macri's predecessor Cristina Kirchner had refused to pay the holdouts. She insisted that they should have joined in with the 93 percent of the country's creditors that accepted a significant reduction in what they were owed to help the country restructure its finances.

Kirchner branded the hedge funds which led the holdout claims, NML Capital, a unit of Elliott Management, and Aurelius Capital Management as "vultures", saying they bought up Argentine debt cheaply around the time of the default and then refused to take part in the restructuring so that they could pocket huge profits.

Both hedge funds had yet to say whether they accept or reject the new offer by Buenos Aires.

The funds which accepted the offer were Montreux Partners and Dart Management, according to the government.

Subject to conditions

Al Jazeera's Daniel Schweimler, reporting from Buenos Aires, said: "The dispute is not yet over but certainly with this latest agreement in New York, after five days of very intense negotiations, huge steps forward have been made.

"There's been a definite move on both sides ... to change the whole mood of the negotiations - to try to reach some kind of resolution."

Schweimler said Macri was keen to end the dispute and open the economy to much-needed foreign investment.

"Reserves are very low, investment isn't coming in, so they're hoping here in Buenos Aires that they're on the way to solving this long-running dispute."

Pollack said more work "remains to be done" on the proposal, which was subject to two conditions: firstly, that it gains approval by Argentina's Congress; and secondly, that it also brings the release of the New York federal court's injunction, which prevents Buenos Aires from paying any other creditors outside the so-called holdout group.

Macri took power in December without a majority in the legislature, and Kirchner's bloc remains powerful, though it showed signs of fragmenting this week.