Touched upon at their meeting were the joint history and century-long good relations between Estonia and the U.K., according to an Office of the President press release.

"The United Kingdom was a staunch supporter of Estonian statehood thoughout the Soviet occupation," Kaljulaid said following their meeting. "They are our closest allies also today."

The Estonian head of state also presented the queen with a jar of last summer's honey from the Kadriorg Rose Garden.

Later that day, Kaljulaid opened a business seminar organized by the Estonian Chamber of Commerce and Industry, where Estonia introduced its economic and legal environment to British media service providers. She also gave the second of two public lectures on this visit at University College London.

The Estonian president on Tuesday met with British Minister for the Cabinet Office David Lidington, visited Imperial College London, where she also met with a number of Estonian students studying there, and gave a public lecture at Chatham House on the topic of coping with the digital transition.