0905 : Far-left members of Greece's ruling Syriza party have revealed plans to form a splinter party, Popular Unity, following the resignation of Prime Minister Alexis Tsipras and calling of snap elections overnight.
Refer to the input text as context and select the correct relationship between 'Syriza' and 'Alexis Tsipras' from the available options.
Options: employer, chief executive officer, chairperson, product/material produced