Presidents have relied on their fast-track Trade Promotion Authority (TPA) to negotiate pacts that Congress can ratify or reject but not amend.

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Chuck Grassley, R-Iowa, the top Republican on the Senate Finance Committee, talked about the challenges ahead in pushing through presidential "fast track" trade promotion authority and in crafting a prescription drug benefit for Medicare, something GOP pollsters say is essential to complete before the next election.

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President Bush is lobbying Congress to renew his "trade promotion authority, " a fast-track approval for trade deals that expires at the end of June.

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He and President George Bush may now find it difficult to obtain trade-promotion authority, formerly known as fast-track, from Congress: this enables the American team to work towards a deal and put it to Congress on a take-it-or-leave-it basis, rather than enabling the legislators on Capitol Hill to unpick it line-by-line.

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But the Police Federation, the policemen's trade union, is strongly opposed to fast-track entry which would give high-fliers on short-term contracts accelerated promotion into senior ranks without having to serve on the beat as a constable.

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