Visa Europe has notified mobile banking software provider Monitise that it plans to sell its shares in the firm.
It is another blow for the British firm, which is currently in the midst of a business transformation programme as it attempts to return to profitability through a shift to cloud-based revenues.
The payments firm had reportedly been considering selling its stake in Monitise since last year.
Visa Europe has been a shareholder in the UK firm since October 2011. It currently holds 115,750,000 shares in Monitse, equal to a 5.3 percent stake in the company.
Monitise said in a statement that it will continue to work with Visa Europe on a "number of projects and services" as part of a three-year agreement that continues to 2016.
However, the share sale casts doubts over a longer standing relationship between the two companies.
Monitise said both parties will "assess on an ongoing basis opportunities to work together in future" following the end of the three-year commercial agreement.
Last year a number of staff joined the Monitise from Visa Inc, including CEO Elizabeth Buse, who replaced co-founder Alistair Lukies as he stepped down from his role earlier this year.
It has also partnered with IBM to support Visa Europe's mobile payment business.
Earlier this week, the company issued a profit warning in its full year financial results, with revenues expected to be lower than previously expected.
However, the company has shown signs of a revival, bagging a deal with Socite Generale in May, and securing a multi-million pound payment through a fintech investment venture with Santander earlier this month.