Complex sentence: Harper was also granted an audience with the Queen at Buckingham Palace on 5 June, after which he, the Governor General, and Queen Elizabeth unveiled a new portrait of the sovereign commissioned by the federal Crown-in-Council.
Split into simpler sentences: Harper was also granted an audience with the Queen at Buckingham Palace on 5 June. At Buckingham Palace on 5 June, the Governor General, the Prime Minister, and Queen Elizabeth unveiled a new portrait of the sovereign commissioned by the federal Crown-in-Council.