Shapps initially entered the race on Sunday (10 July) after former prime minister Boris Johnson announced his resignation, but then pulled his name from contention only 48 hours later on Tuesday (12 July).
Via Twitter, he said: "Huge thanks to my team for helping to pull together my leadership bid in literally no time.
"Amongst a field of brilliant candidates, I’ve spoken to Rishi Sunak who I believe has the competence and experience to lead this country."