LONDON, Jan 23 (Reuters) - Britain should consider launching a social tariff for household energy prices which would see those most vulnerable and least able to pay charged a lower price for their power, the country's energy regulator said on Monday.

British energy prices hit record highs last year, forcing the government to subsidise costs for all households and issue extra payments for the most vulnerable.

Even with this help "there are many households that simply cannot pay their energy bills", Ofgem Chief Executive Jonathan Brearley said at an Institute of Government event.

The government has guaranteed to keep average household energy bills below 2,500 pounds ($3,086) a year until the end of April and below 3,000 pounds until March 31, 2024.

However these costs are still around three times higher than people were paying before the pandemic and before Russia's invasion of Ukraine sparked record high prices in Europe's electricity and gas markets.

Brearley said it was unlikely that prices would return to pre-pandemic levels and that the energy crisis sparked after Moscow sent troops into Ukraine meant new approaches were needed in Britain's energy sector. (Reporting By Susanna Twidale)