TEGUCIGALPA, Dec 7 (Reuters) - Honduran electoral authorities on Tuesday began an unprecedented recount of some of the ballots from last month"s congressional elections after allegations of fraud and inconsistencies at some of the ballot boxes. Leftist politician Xiomara Castro won the presidency in the general elections on Nov. 28 but her ability to implement sweeping social reforms will depend on the balance of power in Honduras" single-house National Congress. Congressional candidates from Castro"s Liberty and Refoundation party and its ally, the Salvador Party of Honduras, have accused the ruling National Party of "inflating" the vote tally in their favor. Preliminary results give 61 seats to Castro"s party and its ally, with 43 seats going to the National Party, 22 to the Liberal Party and the remaining to minority groups. Under a vote verification and counting process, the votes cast at 2,581 ballot boxes - representing 14% of voting stations nationwide - will be recounted. Kelvin Aguirre, an official with the country"s electoral council, said other contested ballots will also be scrutinized. It is the first such recount since the Central American country started holding free elections in 1982 following almost two decades of military dictatorship. Castro, who would assume power on Jan. 27 if the final results confirm her broad advantage, has announced that she will repeal several laws that shield officials and deputies accused of corruption. Her main opponent, Nasry Asfura of the National Party, has recognized Castro"s win. In the coming year, the Honduran Congress will elect a new supreme court as well as a new attorney general. Based on the current preliminary vote count, Castro and her allies would need two-thirds of the votes to push through their candidates, which could only be reached by uniting with the opposition, analysts said. To change most laws, they would need a simple majority.