MADRID (Reuters) - The Spanish foreign ministry said on Monday it had asked North Korea s ambassador to leave Spain before the end of the month due to his country s repeated refusals to renounce its nuclear weapons program.  Today, the North Korean ambassador was summoned and was told of the decision to consider him as a persona non grata, therefore he must stop working and abandon the country before Sept. 30,  the foreign ministry said in a statement. The United Nations Security Council imposed new sanctions after North Korea s sixth and largest nuclear test this month, and the United States called on countries to sever diplomatic and financial ties with it. 