[168][169] Polk came to believe that Scott was too slow in getting himself and his army away from Washington and to the Rio Grande, and was outraged to learn Scott was using his influence in Congress to defeat the administration's plan to expand the number of generals.[170] The news of Taylor's victory at Resaca de la Palma arrived then, and Polk decided to have Taylor take command in the field, and Scott to remain in Washington. Polk also ordered Commodore Conner to allow Antonio López de Santa Anna to return to Mexico from his exile in Havana, thinking that he would negotiate a treaty ceding territory to the U.S. for a price. Polk sent representatives to Cuba for talks with Santa Anna.
Polk sent an army expedition led by Stephen W. Kearny towards Santa Fe, to territory beyond the original claims in Texas.[171] In 1845, Polk, fearful of French or British intervention, had sent Lieutenant Archibald H. Gillespie to California with orders to foment a pro-American rebellion that could be used to justify annexation of the territory.