Greek Prime Minister Alexis Tsipras is also under pressure from many in his radical left Syriza party who say the new accord will pile further austerity on a weakened economy and goes against the party's campaign pledges.
Utilize the input text as a context reference, choose the right relationship between 'Syriza' and 'Alexis Tsipras' from the options.
Options: distributed by, subsidiary, legal form, chairperson