Queen will be hosting US President Joe Biden at Buckingham Palace in her first major diplomatic engagement since she left the capital during the coronavirus pandemic.Her Majesty, 94, says she is "determined to get back to business" after being prevented from carrying out her public duties during the last year of lockdowns and coronavirus restrictions.The new US president and other world leaders will be visiting the UK as part of the G7 summit in Cornwall in June.Prince Charles, Prince William and the duchesses of Cornwall and Cambridge will be reportedly joining the Queen for the 'soft power' reception.Reports say a one-on-one meeting with Biden and the monarch is also due to take place, her first diplomatic engagement following her planned.