Johnson was elected new Conservative Party leader in a vote on Tuesday and will replace Theresa May as the next UK prime minister.
Johnson, who received 92,153 votes, beat Jeremy Hunt who received 46,656.
In a formal letter following the election, President Barzani conveyed his congratulations to the British official.
“I extend my warmest congratulations on your election as the leader of the Conservative Party,” the letter published on the Kurdistan Regional Government’s (KRG) Presidency website read “I am certain that your experience and leadership will prove invaluable for the United Kingdom.”
President Barzani underlined Kurdistan’s pride regarding its ties with Britain and said he hopes “the relations between the Kurdistan Region and the UK will improve further” following Johnson’s election.
The Kurdish leader highlighted “the UK’s instrumental support” to Kurdistan in the fight against the so-called Islamic State, describing it as “vital.”
“Our Region will count on the continued support of the UK under your leadership for maintaining stability in this important part of the Middle East,” the letter concluded.
In 2015, Johnson, then-Mayor of London, visited the Kurdistan Region and accompanied Peshmerga fighters on the front lines.
The British official previously commended the role of the Kurdish Peshmerga in defeating the Islamic State in an interview with Kurdistan 24 in September 2017, days before the historic independence referendum.
Johnson also notably encouraged then-Iraqi Prime Minister Haider al-Abadi to lift an airport ban on the autonomous Kurdish region, one of many punitive measures Baghdad had enforced on the Kurdistan Region in response to the referendum.
Editing by Karzan Sulaivany