Crystal Palace have signed Senegal striker Ismaila Sarr from Marseille, the English Premier League club announced on Thursday.

The 26-year-old, who spent four seasons in England with Watford, has agreed a five-year-contract at Selhurst Park.

No fee was disclosed but British media reports said Sarr was heading to France in a deal worth around £12.5 million ($16 million).

"We're happy that Ismaila has decided to join Crystal Palace because he knows the Premier League when he played at Watford, he knows living in England, and he also had many games with Marseille last season," Eagles boss Oliver Glasner said.

"In every year, in every club where he was, he's showed that he can score goals. He showed it as well in the national team for Senegal, so we are really pleased that he will join our group."

Sarr scored 34 goals in 131 appearances for Watford before helping Marseille reach the semi-finals of last season's Europa League.

"I am very happy to be here because Crystal Palace is a great club," said Sarr. 

"Thanks to the coach and the sporting director -- they told me about their project, and I accepted because it is a good project.

"I am going to work hard on the pitch and off the pitch for the team and for the fans as well," he added, with Palace looking to build on last season's 10th-placed finish in the 20-team Premier League.

Newly-promoted Ipswich Town have signed full-back Conor Townsend from West Brom on a two-year deal for an undisclosed fee.

The 31-year-old told TownTV: "To play in the Premier League again is a big challenge for me and this kind of opportunity doesn't come around very often so I jumped at the chance."

Nottingham Forest, who finished just above the relegation zone last season, have bolstered their attacking with the addition of forward Jota Silva.

Jota, 25, has signed a four-year deal at the City Ground after scoring 20 goals in 83 appearances for Vitoria in his native Portugal, with his form last season earning him an international debut in March.