Sterling jumped above $1.42 today, coming within touching distance of $1.43, while also reaching a year's high against the euro as analysts retained their bullish views on the currency.
The pound is the best-performing G10 currency this year, up nearly 4% against the dollar and 3.2% against the euro as investors bet Britain's rapid Covid-19 vaccine rollout will lead to a quicker economic rebound.
Analysts also point to relief over avoiding a "no-deal" Brexit with the European Union at the end of last year as benefiting the pound, with the market looking through short-term headwinds and disruption.
In Asian trading hours, sterling rose to $1.4295 against the dollar, its highest since April 2020. It climbed to its highest against the euro in a year, touching 85.40 pence.
In London trade, sterling was 0.5% higher on the day at $1.4175 and 0.3% higher to the euro at 85.82 pence.
Also supporting sterling has been a pushing back of market expectations of negative rates by the Bank of England.
Bank of England Governor Andrew Bailey is due to testify before the UK parliament's Treasury Committee today, a day after his US counterpart, Federal Reserve Chair Jerome Powell, testified before the US Senate Banking Committee.
"Bailey will face a similar challenge to that faced by Powell yesterday: delivering a cautious and dovish message despite clearly encouraging recovery prospects," strategists at ING said in a note to clients.