I am British, and so is my ex-wife and our child, who moved to Israel a few years ago. What can I do to renew contact with my child, which has stopped since my "ex" remarried in Israel?

Bring legal action at the Israeli family court for contact with your child, which would include meetings/visits in both countries and ongoing virtual contact, by phone and /video-link via technology such as Skype, FaceTime,Whatsapp etc.

Your child has a right under international law to have a relationship with both of his/her parents,even if they live in different countries, and knowledge of/access to his/her cultural heritage. Israel recognizes this right, and associated rights of a child regarding his/her identity/heritage which are enshrined in the 1989 U.N. Convention on the Rights of the Child. The Convention was adopted by Israel and has bound it since 1991.