LibreOffice is a fork of the OpenOffice.org office suite which became the property of Oracle when it bought Sun Microsystems. OpenOffice.org was donated to the Apache Software Foundation by Oracle last year.
LibreOffice kicked off in September 2010 and has become much more widely used than OpenOffice.org.
A media release said the Document Foundation would focus on the technical committees around the Open Document Format - which is the default file format for LibreOffice - and standards therein.
"The Document Foundation's decision to join the OASIS Consortium strengthens the whole ODF ecosystem with the addition of the largest independent free software community focused on personal productivity and office suites, capable of reaching over 95 per cent of the world's population with the most accessible ODF implementation," added Schulz, a former director of OASIS himself.
Olivier Hallot, a volunteer and TDF director, said TDF had always been committed to Open Standards, which are a founding principle of the project.
"Although the project was already represented at OASIS through several corporate and individual members, the board of directors has decided to step in to give voice to the end users and reduce the influence of corporate interests on the future of the Open Document Format," he added.
TDF will hold its second LibreOffice conference in Berlin in mid-October. The three-day event, which is free, will include a dedicated ODF Plugfest, a vendor-neutral interoperability event gathering industry-wide experts of the OpenDocument Format.