First World Peace Conference
The first World Peace Conference was held in London, and its delegates included American Senator Alcott and Chinese General Cheng Teik. The Master used the Keller Machine and a hypnotised Chin Lee to disrupt the conference. He later planned to destroy it with the Thunderbolt missile he hijacked. The Master's scheme was defeated by the Third Doctor and UNIT. (TV: The Mind of Evil)
The conference broke down, leading to an escalating conflict between the superpowers (TV: Robot) of China, the Soviet Union (PROSE: Who Killed Kennedy) and the United States that had the world on the brink of World War III just a year later. (PROSE: Doctor Who and the Day of the Daleks)
Second World Peace Conference
Britain again offered to mediate. The second World Peace Conference was arranged by Sir Reginald Styles and preliminary conference was to be held at Auderly House. As fighting broke out in China and South America, the Chinese threatened to pull out but agreed to attend after Styles visited Peking. The conference was almost destroyed by time-travelling guerrillas from an alternate 22nd century. In their native time period, they believed the conference was destroyed by a treacherous Styles, but they actually became a part of history themselves and their attempt to assassinate Styles and avert the wars instead led to that very outcome. The Third Doctor interfered, saving the delegates from the Daleks and negating the timeline. The Daleks, not the delegates, were blown up with Auderly House. (TV: Day of the Daleks)
The peace plan
The Chinese, the Americans and the Soviets agreed to give details of their hidden atomic missile sites to a neutral country, a role which also fell to Britain. All the secrets would be published in the event of a serious confrontation. The destructor codes for firing these missiles were entrusted to Cabinet minister Joseph Chambers kept in a special Dynastreem safe in his house.
The Scientific Reform Society (SRS) attempted to further disrupt the peace in a bid for power. Using Professor J.P. Kettlewell's K1 robot, they murdered Chambers and stole the codes so they could blackmail the United Nations. The SRS members were all apprehended when UNIT raided their bunker. The rogue K1 was destroyed by the Fourth Doctor after it tried to start a nuclear war to wipe out humanity. (TV: Robot)