The U.N. Secretary-General U Thant to-day [United Nations, Oct. 27] urged Peking to hurry up its appointment of a U.N. representative amid speculation that China could take over leadership of the Security Council on Sunday night. In his second cable to the Chinese Foreign Ministry since Monday night when the General Assembly decided to seat the People’s Republic of China and expel Taiwan, U Thant asked for a swift appointment so that the work of the Security Council might not be interrupted. He observed that a Council member’s delegate must present his credentials not less than 24 hours before taking his seat. The presidency of the Council changes at midnight on Sunday and if the Chinese decided to be known in the U.N. as the People’s Republic of China, it would go to them. Otherwise, Poland will succeed Nicaragua under the system of alphabetical rotation. “I would be grateful if you would inform me at your earlier convenience of the name of your representative on the Security Council, U Thant said in his message to the acting Foreign Minister, Mr. Chi Peng-Fei. “I may add that a meeting of the Security Council might be called any moment by the President.”