Rep. Jared Huffman (D-Calif.) introduced an amendment to a roughly $1 trillion spending package expected to go to the House floor next week that would at least temporarily block the proposed Pebble Mine in Alaska, a Huffman aide said.

Under Huffman’s amendment, the U.S. Army Corps of Engineers would be forbidden from using any funding to complete the environmental impact statement for the massive gold and copper mine, according to a...