Eckert, chairman of the adjudicatory chamber of FIFA's independent Ethics Committee, published the findings of the investigation into the next two competitions on Thursday.
The 42-page document cleared Russia and Qatar, hosts of the 2018 and 2022 World Cups respectively, of corruption claims.
However, both England and Australia came in for criticism for their respective 2018 and 2022 bids, particularly for their supposed attempts to woo the vote of former FIFA vice-president Jack Warner, who resigned from his position in 2011 amid allegations of bribery.
After the report was made public former United States attorney Garcia, who led the investigation by FIFA's Ethics Committee, openly criticised the report by stating there were "numerous materially incomplete and erroneous representations of the facts", while stating he intended to appeal the findings.
Responding to Garcia's statement, Eckert told BBC Sport: "I'm surprised, not shocked. I'm a long time in the job here. I don't think anything surprises me."
Garcia's swift criticism led to calls for Garcia's original findings to be published in full.
However, Eckert reiterated his stance that it is not legally possible to do so.
"I don't think that's possible because I have to respect the rights of confidentiality for continental law," he added.
"Maybe it's another thing in the US, but in continental law I can't do it, and I can't do it in total even by the FIFA code of ethics. I will not do it."
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