Jimmy Carter has praised British police and intelligence services for their "rapidity" in apprehending the four suspects sought in connection with the failed July 21 attacks in London.
President Carter said America stood united with Britain against terrorism.
Speaking at the Baptist World Alliance's centenary conference in Birmingham, the 80-year-old said: "First of all I'm very proud to be in a nation that stands so stalwart against terrorism with us.
"The people of my country have united our hearts and sympathy for the tragedy that you have suffered from terrorism."
He added: "We are filled with admiration and awe at the obvious harmony and cooperation that exists among your law enforcement agencies and intelligence agencies and the rapidity with which you have identified and taken those who are responsible for these atrocities."
President Carter, who was noted for his devotion to the Baptist faith during his time in the White House as the 39th US President, called on people of all faiths who believed in freedom, peace, justice, hospitality and alleviation of suffering to work together in a bid to defeat terrorism.
He said: "I think if you concentrate on these things, that would make the united front against terrorism more effective.
"We should try and identify the things that divide us and set them aside ... and build a common commitment."
President Carter, who took a Bible class at the conference, reiterated his belief that the invasion of Iraq was " unnecessary and unjust" and that Guantanamo Bay was an "embarrassment".
"I think what's going on in Guantanamo Bay and other places is a disgrace to the USA," he said.
"I wouldn't say it's the cause of terrorism but it has given impetus and excuses to potential terrorists to lash out at our country and justify their despicable acts.
"It may be an aggravating factor but it's not the basis of terrorism."
Organisers of the event last night said it had gone without a hitch.
More than 13,000 delegates from 170 countries attended the conference at the city's International Convention Centre.
The visitors are expected to have spent millions of pounds on entertainment, accommodation and travel in the West Midlands.
The conference was the largest international Christian gathering to have been
held in Britain for 50 years. Weeks before, organisers were forced to consider whether they should hold the event in Birmingham as planned in light of recent terror scares and the London bombings.
Chris Hall, from the World Baptist Alliance, described Birmingham as the perfect host.
He said: "The city has been superb. It is ideally geographically placed and very compact. Baptists from across the globe have been very impressed with Birmingham's canals and the friendliness of its locals.
"We are all very thankful that the city agreed to host us because 13,000 is a lot of people and a lot of responsibility. We have been using every hall at the ICC."
The conference was held in the UK to mark the birth of the World Baptist Alliance 100 years ago in London.
Among the issues discussed were Aids, poverty, Third World debt, justice and human rights abuses.
The World Baptist Alliance has a community of 100 million people scattered across the globe and 211 different member bodies.
Most visitors to the congress were from the United Kingdom, the United States, Nigeria, India and South Korea.