1. Is there a ban on donations from foreign interests to political parties?

Article 4, Law on Financing of Political Organisations (Parties), the amended version of law 01.12.2017 in force from 01.01.2018, No.  114 (397).

Only citizens and persons who have the right to receive an Aliens passport of the Republic of Latvia are allowed to make donations for political parties.

Section 4. Gifts (Donations)
(1) In accordance with the restrictions referred to in Section 6 of this Law, political organisations (parties) may accept gifts (donations) from:
1) Latvian citizens;
2) persons who in accordance with law have the right to receive an Aliens passport of the Republic of Latvia;