The White House
Presidents have claimed executive privilege, the right to withhold information from One of the Presidents powers that is unshared with Congress, is his ability to receive foriegn Ambassadors and representatives. By receiving Ambassadors the President can thus grant recognition to foreign governments.
The constitution states: that “the President shall receive ambassadors and other public ministers”. On the surface that does not seem to be an important power, however by receiving ambassadors the President effectively can recognize new countries or governments. This is a power that the President does not share with Congress. It is a unilateral power. The power has been very significant a number of times, including the American recognition of the French Republic, as well as the prompt Recognition of Israel by President Truman. The power to recognize a nation or government unilaterally can have a significant impact on foreign relations.