In June, the ITF Executive Board gave their backing to a series of changes affecting both the men’s Davis Cup and the women's Fed Cup, including a recommendation to shorten the length of contests in the former.

But the motion was backed by less than the two-thirds majority of voters needed in Ho Chi Minh City, with 63.54 per cent support being received from member nations.

"We respect the decision of the AGM but are disappointed that our member nations have not approved the full package of Davis Cup and Fed Cup reforms endorsed by the ITF Board," ITF President David Haggerty said.

"Change is needed to ensure the long-term future of these iconic and historic competitions, and we remain committed to working with our national associations and other stakeholders on finding ways to enhance Davis Cup and Fed Cup by BNP Paribas."

A landmark resolution was passed today, however, giving the ITF Board of Directors the authority to make changes to Davis Cup and Fed Cup regulations on a trial basis without needing to seek approval from the general membership.

The amendment received overwhelming support at the close of the AGM. 

The resolution was submitted for vote based on feedback from the delegates in Vietnam indicating that they have confidence in the Board members to make changes they deem necessary to enhance the ITF’s flagship team competitions.

Previously, changes to the Davis or Fed Cup regulations could be only be made annually at the AGM. 

"This is a ground-breaking decision," Haggerty added.

"The resolution gives the Board the latitude and flexibility of trialling changes to Davis Cup and Fed Cup without waiting for approval of the AGM. 

"In a fast-changing world, we need to be agile and nimble to make decisions, and this resolution gives us that ability. 

"We thank our members for their support in the ITF Board."

Among the other proposals approved today was guaranteeing both the Davis Cup and Fed Cup finalists the choice of hosting their first-round ties the following year.

Match court availability and practice court requirements will be lower to reduce hosting costs for national associations.

The members also passed a motion to reduce Davis Cup pre-tie commitments for players to a single function combining the draw, post-draw press conferences and interviews and an official lunch.

Haggerty, the American voted into the top job to replace Italy's Francesco Ricci Bitti in September 2015, said earlier this week he believed the changes to the Davis Cup and Fed Cup were vital to safeguard the flagship events.

The competitions have suffered due to a packed tennis schedule which has led to the top players often not seeing them as a priority and dropping out.

World number one Sir Andy Murray has previously called for Davis Cup matches to be shortened to increase the participation of the sport’s biggest stars.

"The ITF must lead and this week I need your support to ratify the significant changes that will strengthen the ITF," Haggerty said on Wednesday (August 2).

"This week we must think about what is best for the ITF."

A new World Cup of Tennis is due to be established, featuring both the Davis Cup final and the Fed Cup final.

A decision to announce Swiss city Geneva as the first host in November 2018 has been deferred until next year following feedback from players and fans.