The king of Bahrain, whose regime has been accused of suppressing pro-democracy demonstrations, has been revealed as one of the guests at a historic lunch of sovereign monarchs hosted by the Queen at Windsor Castle on Friday, according to the British newspaper, The Guardian. King Hamad bin Isa al-Khalifa appeared on a guest list released early Friday, ahead of the unprecedented gathering to celebrate the diamond jubilee. Other guests on the list include Swaziland\'s King Mswati III, Sheikh Nasser Mohamed al Jaber al-Sabah of Kuwait and Prince Mohammed bin Nawaf bin Abdulaziz al-Saud of Saudi Arabia. However, a definite no-show to the event, will be Queen Sofía of Spain, who was ordered by her government to turn down the invitation in response to a planned trip next month by the Earl of Wessex to Gibraltar. Spain wants the UK to return Gibraltar and this issue has been a thorn in the side of bilateral relations between Madrid and London. Human rightsdemonstrators are expected to stage a protest outside Bahrain\'s embassy in London later Friday, over the inclusion and proposed visit of the Bahraini sovereign. Denis MacShane, the former foreign office minister accused the FCO of placing the Queen in an impossible position, saying: \"Many in Britain will regret that the foreign secretary, who approves all invitations sent in the Queen\'s name as head of state, has decided to include a representative of the Bahraini regime which has done such terrible things to its own people since the Arab awakening a year ago.\" The foreign office said that: “all world sovereigns were invited to the event, which was \"organised by the royal household, with assistance and co-ordination by the FCO\". It added that the UK was a \"long-standing friend and ally\" of Bahrain, and the \"strong relationship\" allowed \"full and frank discussion\" on issues of concern, including human rights. The FCO added that the UK government supported reforms already under way, and wants to help promote that reform, including moves to bring to account individuals responsible for human rights abuse. Peter Tatchell, a human rights campaigner, was critical of the inclusion of eight of the monarchs on the Queen\'s guest list, saying: \"It is outrageous that the Queen has invited royal tyrants to celebrate her diamond jubilee. She should not host the monarchs of countries such as Brunei, Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, Swaziland and United Arab Emirates.\" Tatchell added: \"All eight royal families preside over a variety of human rights abuses, such as detention without trial, torture, the denial of free speech, restrictions on press freedom, discrimination against women, oppression of minority faiths, homophobic persecution, ill-treatment of guest workers and the violent suppression of peaceful protests\". The Guardian also adds, that the Queen is rolling out the full red-carpet treatment, inviting the Duke and Duchess of Cambridge, as well as Prince Harry and princesses Beatrice and Eugenie, to the lunch. Prince Charles is hosting his own dinner for foreign royals at Buckingham Palace on Friday night, although without the king of Bahrain. Recent reports by Amnesty International highlighted a wave of repression in Saudi Arabia as the authorities crack down on protesters and reformist, while Human Rights Watch has criticised the Kuwaiti authorities for the suspension of a daily paper and the conviction of its editor for alleged incitement. European royals attending include King Carl XVI Gustaf and Queen Silvia of Sweden, King Harald V and Queen Sonja of Norway, Prince Albert II of Monaco and his wife, Princess Charlene.