To do that we need to think carefully about locally - driven electoral alliances to beat Conservative candidates. (compassonline.org.uk)
Distinct from the process of electoral alliances in that the political parties remain separately listed on the ballot, the practice of electoral fusion in jurisdictions where it exists allows minor parties to influence election results and policy by offering to endorse or nominate a major party's candidate. (politics.stackexchange.com)
The possibility of combination of party lists for elections existed in the Dutch electoral system between 1973 and June 2017 as a weak form of electoral alliance between two parties. (en.wikipedia.org)