Prince Harry will announce his engagement to Meghan Markle on August 4.

Meghan Markle

Meghan Markle

The happy couple - who have been dating since last year - are reportedly set to announce Prince Harry's expected proposal in three months time as not to overshadow some big political and state events for the UK in the coming months.

A source told the Daily Mail newspaper: "They are not engaged formally but there is an understanding. The engagement announcement is still tipped for August 4 and is unlikely to come earlier.

"Why so? Because the general election (June 8), the formation of a new government (June 9), the State Opening of Parliament (June 19) and the state visit of King Felipe of Spain (July 12-14) cannot be overshadowed."

Prince Harry confirmed he was dating Meghan when Kensington Palace released a statement in November saying how "disappointed" the flame-haired royal is that he hasn't been able to protect the 'Suits' star from the online trolls she has faced since the romance was made public.

The statement read at the time: "His girlfriend, Meghan Markle, has been subject to a wave of abuse and harassment. Some of this has been very public ... the outright sexism and racism of social media trolls and web article comments.

"Prince Harry is worried about Ms Markle's safety and is deeply disappointed that he has not been able to protect her. It is not right that a few months into a relationship with him that Ms Markle should be subjected to such a storm. He knows commentators will say this is 'the price she has to pay' and that 'this is all part of the game'. He strongly disagrees. This is not a game - it is her life and his."