Enner Valencia is undergoing a medical at West Ham United ahead of a proposed £12m move to Upton Park from Mexican side Pachuca, according to the Press Association. 

Valencia, 24, impressed for Ecuador during the World Cup, scoring three goals in as many games as the South Americans exited at the group stage.

The forward is understood to have agreed a five-year deal with the Hammers and will become Sam Allardyce's fifth summer signing after Cheikh Kouyate, Mauro Zarate, Aaron Cresswell and Diego Poyet.

San Lorenzo-born Valencia scored 18 league goals in just 22 starts for Mexican side Pachuca last term, helping the Tuzos finish second in the Clausura Championship.

Ecuador were knocked out of the World Cup in the group stages but not before Valencia scored a brace in the win over the Honduras and netted La Tricolor's consolation in the 2-1 reverse against Switzerland.

Hammers winger Stewart Downing believes the addition of the forward will be an important addition at Upton Park and told the Daily Mirror: “We can't rely on Andy all season.

“And from what I’ve seen of Valencia against England, he looks a very good player.

“He can nick a goal and it is competition for places. It’s what we’ve needed as we didn’t have that last season.”