Boris Johnson's popularity among Conservative voters has taken a big hit in the past two months according to polling from YouGov.

Mr Johnson has come under fire over the past week over his handling of the imprisonment of Nazanin Zaghari-Ratcliffe in Iran, and his latest approval scores are unlikely to improve mood.

In September - around the time he published his vision for Brexit in the Telegraph - the Foreign Secretary's approval among the general populous stood at -17 but was a healthy +35 among people who voted Conservative earlier in the year.

However, the latest set of polling - conducted at the end of last week - shows that Johnson's net approval score among Conservative voters has plummeted to +12 with 40 per cent now holding an unfavourable view of him.