BUENOS AIRES (AFP) - Argentine President Cristina Kirchner was recovering "without complications" on Wednesday from surgery that successfully removed a blood clot on her brain, her doctors said.

"Her spirits are very good," according to the medical report.

Mrs Kirchner, 60, underwent surgery on Monday after being diagnosed over the weekend with a "chronic subdural hematoma" resulting from a blow to the head sustained in a fall in mid-August.

"On the first post-operative day, Kirchner is evolving favorably without complications," the report said.

"Her vital signs are within the normal range" and she remains under close medical supervision, it added.

Vice-President Amado Boudou, a former economy minister, has assumed day to day running of the government, although without a formal transfer of presidential powers.

"The decisions are taken by the president, who gives the instructions, and they are executed by the president in charge," Cabinet chief Juan Manuel Abal Medina said on Del Plata radio.

Mrs Kirchner's convalescence comes as the country heads into mid-term parliamentary elections Oct 27 that are likely to set the political tone for the last two years of her presidency.

At stake are half the seats in the lower house of Congress and a third of the Senate. Mrs Kirchner's Peronist party currently controls both houses, but showed signs of weakness in primaries earlier this year.