Updated

Leaders on both sides of the Atlantic mourned the death Monday of former British Prime Minister Margaret Thatcher:

President Obama

"With the passing of Baroness Margaret Thatcher, the world has lost one of the great champions of freedom and liberty, and America has lost a true friend. As a grocer's daughter who rose to become Britain's first female prime minister, she stands as an example to our daughters that there is no glass ceiling that can't be shattered. As prime minister, she helped restore the confidence and pride that has always been the hallmark of Britain at its best. And as an unapologetic supporter of our transatlantic alliance, she knew that with strength and resolve we could win the Cold War and extend freedom's promise. Here in America, many of us will never forget her standing shoulder to shoulder with President Reagan, reminding the world that we are not simply carried along by the currents of history-we can shape them with moral conviction, unyielding courage and iron will. Michelle and I send our thoughts to the Thatcher family and all the British people as we carry on the work to which she dedicated her life-free peoples standing together, determined to write our own destiny."

Senate Republican Leader Mitch McConnell

"Americans and all freedom-loving people around the world mourn the passing today of The Iron Lady, Margaret Thatcher. A shopkeeper's daughter from Lincolnshire, Margaret Thatcher rose through the force of her will and the power of her arguments to become the first and only female Prime Minister Great Britain has ever had. Undaunted by the tremendous personal and political obstacles that stood in her path at nearly every turn, including an attempt on her life, Thatcher reshaped Britain from the state of economic and social turmoil in which she found it to a place of opportunity and promise during three terms in office. She boldly reasserted her nation's strength in foreign affairs, and she became an iconic symbol of the transformative power of conservative ideas. A great ally and admirer of the United States and a trusted partner of Ronald Reagan during some of the most challenging days of the Cold War, Margaret Thatcher never hesitated to remind Americans of their own obligations to the cause of freedom and of the need for political courage and confidence in the face of long odds. A towering figure of 20th century politics and an inspiration to millions around the globe, Margaret Thatcher set a standard of leadership that will be hard to replicate, but which will forever stand as a model for those who wish to change society for the better."

House Speaker John Boehner

"The greatest peacetime prime minister in British history is dead. Margaret Thatcher, a grocer's daughter, stared down elites, union bosses, and communists to win three consecutive elections, establish conservative principles in Western Europe, and bring down the Iron Curtain. There was no secret to her values - hard work and personal responsibility - and no nonsense at all in her leadership. She once said, 'Defeat? I do not recognize the meaning of the word.' Now this lady who was never for turning goes to rest as grateful friends and allies around the world mourn her passing and pray for her loved ones. Americans will always keep Lady Thatcher in our hearts for her loyalty to Ronald Reagan and their friendship that we all admired. At this difficult hour, I send the condolences of the U.S. House of Representatives to Prime Minister Cameron and the British people."

Nancy Reagan

"I am terribly saddened today to learn of the death of Margaret Thatcher. The world has lost a true champion of freedom and democracy. It is well known that my husband and Lady Thatcher enjoyed a very special relationship as leaders of their respective countries during one of the most difficult and pivotal periods in modern history. Ronnie and Margaret were political soul mates, committed to freedom and resolved to end Communism. As Prime Minister, Margaret had the clear vision and strong determination to stand up for her beliefs at a time when so many were afraid to "rock the boat." As a result, she helped to bring about the collapse of the Soviet Union and the liberation of millions of people. Ronnie and I knew her as a dear and trusted friend, and I will miss her. The United States knew Margaret as a spirited and courageous ally, and the world owes her a debt of gratitude. My heart goes out to Mark, Carol and the entire Thatcher family."

Former President George H. W. Bush

"Barbara and I were deeply saddened to learn of Baroness Thatcher's passing, and extend our heartfelt condolences to her children and loved ones. Margaret was, to be sure, one of the 20th Century's fiercest advocates of freedom and free markets -- a leader of rare character who carried high the banner of her convictions, and whose principles in the end helped shape a better, freer world. The personal grief we Bushes feel is compounded by the knowledge that America has lost one of the staunchest allies we have ever known; and yet we have confidence that her sterling record of accomplishment will inspire future generations. May God bless the memory of Margaret Thatcher."

Former President Bill Clinton 

"I was saddened to learn of the death of Lady Margaret Thatcher. The United Kingdom has lost its first woman Prime Minister, an iconic stateswoman, and a fearless leader. The United States has lost one of its dearest friends and most valued allies. Lady Thatcher understood that the special relationship which has long united our two nations is an indispensable foundation for peace and prosperity. Our strong partnership today is part of her legacy. Like so many others, I respected the conviction and self-determination she displayed throughout her remarkable life as she broke barriers, defied expectations, and led her country. Hillary, Chelsea, and I extend our condolences to her family and to the people of the United Kingdom."

Former President George W. Bush

"Laura and I are saddened by the death of Baroness Margaret Thatcher. She was an inspirational leader who stood on principle and guided her nation with confidence and clarity. Prime Minister Thatcher is a great example of strength and character, and a great ally who strengthened the special relationship between the United Kingdom and the United States. Laura and I join the people of Great Britain in remembering the life and leadership of this strong woman and friend."

Former British Prime Minister Tony Blair

"Margaret Thatcher was a towering political figure. Very few leaders get to change not only the political landscape of their country but of the world. Margaret was such a leader. Her global impact was vast. And some of the changes she made in Britain were, in certain respects at least, retained by the 1997 Labour Government, and came to be implemented by governments around the world. As a person she was kind and generous spirited and was always immensely supportive to me as Prime Minister although we came from opposite sides of politics. Even if you disagreed with her as I did on certain issues and occasionally strongly, you could not disrespect her character or her contribution to Britain's national life. She will be sadly missed."