Javier Hernandez has said he rejected offers from La Liga and Serie A to return to the Premier League with West Ham because of the "confidence and trust" they showed in him.

Hernandez, 29, left Bayer Leverkusen to join West Ham in a £16 million deal two years after leaving Manchester United.

The Mexico international said the lure of playing in the Premier League was too much to resist.

"It was a little bit simple really," Hernandez told a news conference. "I'm in the best league in the world and West Ham showed me a lot of confidence and trust.

"West Ham is showing more ambition compared to the last seasons. They want to qualify for Europe, you can see that in the transfer window. That's why I'm here.

"They're one of the most historic teams in England, very ambitious this season and hopefully we can achieve our goals.

"There were other options -- one in Spain and two in Italy. The last two transfers I made on the last day, this time it was more calm and easy. Thankfully I'm where I want to be."

Hernandez could make his Premier League debut for West Ham against Manchester United at Old Trafford but he isn't daunted by the prospect of facing his former side.

"I'm going back to my old club -- my old house -- and it's going to be very special," he added. "But I'm defending other colours now. I want to help my team win three points and start the season on the right foot."