Britain suffered further blows to its economic standing last Monday as two top ratings agencies downgraded its sovereign credit score, judging the vote to leave the European Union would hurt its economy.
Standard And Poor's stripped Britain of its last remaining top-notch credit rating, dropping it by two grades from "AAA" to "AA" and warning more downgrades could follow.
Fitch Ratings also downgraded its ranking for Britain's creditworthiness by one notch, and similarly said more cuts could follow.
The ratings agencies effectively added a rubber stamp to the market's view of the Brexit vote, as sterling tanked to a 31-year low against the U.S. dollar and stock markets fell for a second trading day since the referendum.
It was the first time SP had chopped an AAA-rated sovereign credit rating by two notches in one move.
The British pound fell to a three-decade low and the pan-European stock index suffered its worst two-day decline in more than seven years.
"In our opinion, this (referendum) outcome is a seminal event, and will lead to a less predictable, stable, and effective policy framework in the UK," SP said in a statement.
Big banks have already begun to take action to shift operations out of the UK. A quarter Britain companies planned to freeze recruitment, with 5% planning to cut jobs, a survey by the Institute of Directors found.