WASHINGTON (Reuters) - A proposed tax on $2.6 trillion in foreign profits held offshore by U.S. multinational corporations would be raised under an amendment offered on Thursday by the chairman of the U.S. House of Representatives tax committee to his own tax-cut bill. Texas Republican Representative Kevin Brady called for raising the tax to 14 percent for cash and liquid assets and 7 percent for illiquid assets, up from his earlier proposal of 12 percent and 5 percent, respectively. The proposed increase would raise more federal revenue under the tax bill being offered by House Republicans, with Senate Republicans offering a separate bill. 