What is the relationship between Syriza and Alexis Tsipras in the context of the input sentence. Choose an answer from: product/material produced; manufacturer; distributed by; industry; position held; original broadcaster; owned by; founded by; distribution format; headquarters location; stock exchange; currency; parent organization; chief executive officer; director/manager; owner of; operator; member of; employer; chairperson; platform; subsidiary; legal form; publisher; developer; brand; business division; location of formation; creator.

The split appears complete between Greek Prime Minister Alexis Tsipras and close to a third of the 149 lawmakers from his radical left Syriza party who have expressed their opposition to the terms of a third bailout.

Answer: chairperson