It said it offered slots to the National Democratic Institute (NDI) and the International Republican Institute (IRI) after the authorities in Myanmar, also known as Burma, invited Washington to send two observers.
State Department spokeswoman Victoria Nuland identified the two as NDI`s Peter Manikas and IRI`s Johanna Kao.
"They`ll be there March 28th through April 3rd to study the conduct and significance of the polling," Nuland said.
But since they will only arrive three days before the vote, they "will not be in a position to monitor in the traditional sense under the terms of the UN Declaration of Principles on International Election Observance," she said.
"So the process that the Burmese have offered, although a positive advance over past elections, is not going to conform to international standards for conducting an election observation mission," Nuland said.
"But they are going to bear witness to how the voting goes forward, and we also are expecting some American journalists and international journalists there," she said.
The European Union, Australia, Japan, and the Association of Southeast Asian Nations (ASEAN) have also announced they would be sending monitors to oversee the by-elections.
The vote, which will see Nobel laureate Aung San Suu Kyi stand for a seat in parliament for the first time, comes a year after a quasi-civilian government took power following the end of decades of outright military rule.
Myanmar did not allow foreign observers for its 2010 election, which swept the army`s political allies to power amid widespread complaints of cheating and intimidation.
But since taking office a year ago, President Thein Sein has surprised even some critics by carrying out reforms including signing ceasefire deals with ethnic minority rebels and releasing hundreds of political prisoners. (*)
Editor: Kunto Wibisono
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