The Secretary of State after talks with the US Secretary of State Mike Pompeosaid he had made clear Britain's "absolute" commitment to the deal.
The government has come under fire from the EU for the UK's Single Market Act, which would allow ministers to override parts of the Brexit deal on trade with Northern Ireland.
Mr. Raab, who is in Washington for talks with high-profile figures, said he had "very positive conversations" with Republicans and Democrats.
He said: "It is a great opportunity to make clear that the threat to the Good Friday Agreement, as reflected in the Northern Ireland Protocol, comes from the EU's politicization of the issue, and to make clear how this happened and why has happened."
"The British action here is defensive about what the EU is doing. It is precautionary, we have not done any of this and it is proportionate," he said.
"What we cannot have is the EU's drive to establish a regulatory border between Northern Ireland and Great Britain along the Irish Sea."
Mr. Raab will meet with US House Speaker Nancy Pelosi later on Wednesday.
His comments came after Ms. Pelosi warned Congress that she would never enter into a free trade agreement with the UK if legislation repealing the Brexit divorce deal "jeopardized" the peace process.
Video: EU is considering legal action against UK over plan to break Brexit deal (Reuters)
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