Euell has struggled to impress new Charlton boss Iain Dowie

Jamaica international Euell travelled to Teesside on Wednesday after Boro were given permission to talk to him.

Boro's chief executive Keith Lamb confirmed to the club's website that the deal had been completed.

The 29-year-old joined Charlton from Wimbledon for �4.75m in July 2001, but has not featured so far this season under new Addicks' boss Iain Dowie.

Boro boss Gareth Southgate is looking for different attacking options following Jimmy-Floyd Hasselbaink's departure for Charlton during the summer.

Euell was Charlton's top scorer for three successive seasons under previous boss Alan Curbishley.

Lamb also quashed speculation that Mark Viduka and Stewart Downing would be exiting the Riverside, saying both were staying put.