Mr Erdogan said his three-day visit would also focus on increasing Turkey-Britain trade.
The Turkish president said bilateral cooperation between the two countries has grown, especially since the referendums that changed Turkey's governing system to an executive presidency and paved the way for Britain's departure from the European Union.
Erdogan added that they were aiming for a $20-billion trade volume between the two countries.
"Trade has always been a locomotive in our bilateral relations, in the last 15 years the United Kingdom has invested over $15 billion in Turkey, that is a sign of trust", Erdoğan said.
Topics include the latest developments in Cyprus, where Turkey and Britain both act as guarantors, and a "joint action plan" for the Middle East, especially Syria, Iraq and Iran.
During telephone conversation with President Recep Tayyip Erdogan, President Rouhani said the JCPOA is a very significant worldwide accord which helps restore global security and stability and a treaty on the Non-Proliferation of Nuclear Weapons.
Turkish President Recep Tayyip Erdogan took a fresh swipe at rating agencies on Friday over the recent downgraded and the negative outlook they have assigned for the Turkish economy, using "bankrupt" Greece as an example.
Erdoğan is expected to meet the CEOs of U.K.'s major companies and invite them to invest in Turkey.
Erdogan said he will speak at Chatham House think thank.