* Former Barca player to join until end of season
* Valencia loan out Postiga, Guardado and Pabon (Adds loan deals)
MADRID, Jan 30 (Reuters) - Valencia have agreed to sign Mali midfielder Seydou Keita on a contract until the end of June with an option for one more season, the La Liga club said on Wednesday.
The deal for the 34-year-old, who played for several French sides before joining Sevilla and then spent four trophy-laden years at Barcelona, is subject to a medical, Valencia said on their website (www.valenciacf.com).
The club had also agreed to loan Portugal forward Helder Postiga to Italian side Lazio, Mexico fullback Andres Guardado to Germany's Bayer Leverkusen and Colombia forward Dorlan Pabon to Sao Paulo of Brazil, they added.
The Postiga and Guardado deals were until the end of the season and subject to medicals and included a purchase option, while Pabon had already passed a medical and was due to play in Brazil until June 2015.
A rangy defensive midfielder who is powerful in the air and has a keen eye for goal, Keita left Barca for Dalian Aerbin in July 2012 following the departure of coach Pep Guardiola. His deal with the Chinese club expired at the end of last year.
Guardiola, who is now at Bayern Munich, used Keita almost exclusively as a substitute and he helped Barca win three Spanish leagues, two Champions Leagues and two King's Cups.
He will give Valencia an extra option in midfield for their Europa League campaign - they play Dynamo Kiev in the last 32 next month - and as they seek to secure a place in Europe again for next season. (Reporting by Iain Rogers, editing by Justin Palmer)