Manchester United have completed the signing of French striker Anthony Martial from Monaco for an undisclosed fee on a four-year deal with the option of a further 12 months. 

The 19-year-old left France's training camp at Clairefontaine on Monday to tie up personal details, having emerged as a target for United following Sunday's defeat at Swansea City.

With Louis van Gaal's side having struggled for goals in the Premier League this term, the Dutchman will hope Martial can help build on his reputation as one of the hottest striking prospects in Europe.

Van Gaal told United's official website: "Anthony is a naturally talented, young, multi-functional forward with great potential. We have been watching him for a while now and he has developed immensely during his time at AS Monaco.

"I am delighted he has joined Manchester United as I believe this is the right club for him to continue his development as a young player. He has all the attributes to become a top football player; however we need to give him time to adjust to his new environment and the rhythm of the Premier League."

Martial said: "I am so excited to be joining Manchester United.

"I have enjoyed my time at AS Monaco and I would like to thank them and the fans for everything they have done for me.

"I have always wanted to play in the Premier League and to join the biggest club in the world is what every young footballer dreams of. I am looking forward to meeting my new team-mates and working with Louis van Gaal who has achieved so much in his career."

Martial has 15 senior goals to his name following spells with Monaco and Lyon and could earn his first senior France cap ahead of this week's friendlies with Portugal and Serbia.