* WFP will target 4.2 million in Syria this month
* Roads in east provinces blocked, airlifts too costly
* As crisis becomes long-term, WFP plans nutrition projects
By Erika Solomon
BEIRUT, Jan 10 (Reuters) - The United Nations World Food Programme has pressed the Syrian government to increase access to besieged residents in Damascus and Aleppo, its chief said, while in eastern Syria a ...