<P> This power exists for urgent or extraordinary situations that require congressional action when Congress is adjourned . Presidents have exercised this power 46 times to recall only the Senate and 28 times to recall both Chambers of Congress, most recently by Harry Truman in 1948 . </P> <P> The Senate itself differentiates between "extraordinary sessions" called by the Presidential proclamation and "special sessions" that merely indicate a session not normally scheduled . The term "session" can refer to either the formal start and end of a Congressional session or the daily sessions of the chambers of Congress . Thus a formal "special session" will only happen when Congress has adjourned sine die and is not simply in recess (in other words Congress may or may not already be in an official session, but in recess, when convened). </P>

True or false the president may only call congress into special session on designated dates