Miller said that Trump is briefed by "a team of policy folks and protocol individuals" prior to conversations with world leaders, but declined to discuss the specific individuals involved in that effort.
He also announced the launch of a national security "landing team" later Thursday which will interact with the State Department, the Justice Department, the Defense Department and the National Security Council as part of Trump's transition.
As Miller told reporters in a call Wednesday night, the national security team will be the first of four "waves." The following three waves will address economic agencies, domestic policy, and independent agencies.
According to a report published Tuesday by the New York Times, foreign allies "were blindly dialing in to Trump Tower" to try and contact the President-elect. Trump took their calls without using official briefing materials from the State Department.
The President-elect fired back on Twitter, calling the transition a "very organized process."
Read the full list of world leaders Trump has spoken to so far, according to a transition team statement quoted by USA Today:
President of Argentina, Mauricio Macri
Prime Minister of the Commonwealth of Australia, Malcolm Turnbull
Prime Minister of Canada, Justin Trudeau
President of the People’s Republic of China, Xi Jinping
President of Colombia, Juan Manuel Santos Calderón
President of the Arab Republic of Egypt, Abdel Fattah al-Sisi
Prime Minister of Denmark, Lars Løkke Rasmussen
Chancellor of the Federal Republic of Germany, Dr. Angela Merkel
President of France, François Hollande
Prime Minister of Ireland, Enda Kenny
Prime Minister of Israel, Benjamin Netanyahu
Prime Minister of Italy, Matteo Renzi
Prime Minister of Japan, Shinzō Abe
King Abdullah II bin Al Hussein of Jordan
Prime Minister of Lebanon, Saad Al Hariri
President of Mexico, Enrique Peña Nieto
Prime Minister of New Zealand, John Key
His Highness Sheikh Tamim Bin Hamad Al-Thani of Qatar
Prime Minister of the Republic of India, Narendra Modi
President of the Republic of Korea, Park Geun-hye
President of the Republic of Turkey, Recep Tayyip Erdoğan
President of the Russian Federation, Vladimir Putin
King Salman bin Abdulaziz Al Saud of Saudi Arabia
Prime Minister of Turkey, Binali Yildirim
President of Ukraine, Petro Poroshenko
President of the United Arab Emirates and Ruler of Abu Dhabi, H.H. Sheikh Khalifa bin Zayed Al Nahyan
Crown Prince of Abu Dhabi and Deputy Supreme Commander of the UAE Armed Forces, Mohammed bin Zayed Al Nahyan
Prime Minister of the United Kingdom, Theresa May
Secretary General to the United Nations, Ban Ki-moon
President of Azerbaijan, Ilham Heydar oglu Aliyev
Prime Minister of The Netherlands, Mark Rutte
President of Poland, Andrzej Duda