David Cameron has won back the support of two leading Tory donors who last summer attacked the "arrogant old Etonian" Conservative leader, with one vowing never to give money to the party again.

The rapprochement with Sir Tom Cowie, the founder of the Arriva transport group, and Lord Kalms, the life president of DSG International, reflects a concerted show of unity by the party at its annual showcase conference. The return of the corporate duo to the Cameron fold also represents a significant shift by business back to the Tories.