Amado Boudou, the economy minister, had been planning to travel to Washington on Wednesday for talks with multilateral lenders as the government put the finishing touches to an offer, due later this month, to the holders of bonds unpaid since Argentina’s $100bn default in 2001.

But a government source said it was not clear whether he would go “if it turns out he’s needed more urgently here”. The source, however, emphasised that the offer to bondholders, who are now owed $29bn (€20bn, £18bn) including interest, would not be derailed.

Argentina has been locked out of capital markets since its default and the offer is crucial to the cash-strapped government’s hopes of a swift return.

“Obviously this isn’t desirable as far as the offer is concerned,” the source said. “But for now markets have been stable and there’s no indication it will complicate matters economically or much less complicate the debt swap.”

Cristina Fernández, Argentine president, last week fired Martín Redrado, central bank governor, by decree after he failed to transfer $6.5bn from the bank’s near record $48bn reserves to a new fund to pay off debt, and then refused her demand to quit.

By Friday night, Mr Redrado was back in his office after a judge upheld an appeal against his ouster and blocked the decree creating the debt-repayment fund.

The government has lodged appeals and María José Sarmiento, the judge, is expected to respond on Monday. Further appeals, to the Supreme Court, are likely to follow.

The crisis has deepened amid political fighting.

Julio Cobos, vice-president, who is leader of the Senate, called on party chiefs to return from summer recess on Monday for a special session on Wednesday of a bicameral commission to look at the use of emergency presidential decrees – called “decrees of necessity and urgency” – such as those used to create the fund and to fire Mr Redrado.

Opposition politicians say there was no “necessity and urgency” in this case since Ms Fernández could have recalled Congress to debate the matter. Ms Fernández, who promised to shore up Argentina’s weak institutions when she took office in 2007, initially boasted of never having to use emergency decrees.

Congress’s intervention in the crisis is likely to be fraught. Mr Cobos is an opposition politician who was at first allied with the government, then broke ranks after casting the deciding vote against Ms Fernández’s plan to raise farm export tariffs in July 2008 and is now seen by some as a presidential candidate in 2011 elections. Néstor Kirchner, Ms Fernández’s husband and former president, blasted him at the weekend for leading an anti-government “conspiracy”.

It was not clear whether opposition lawmakers would heed Mr Cobos’ call to attend Monday’s meeting. Agustín Rossi, a government lawmaker, said Congress could not “summon itself” and only the president could recall legislators from their holidays. Since mid-term elections last year, the government has significantly lost influence in Congress.