NEW YORK (Reuters) -JPMorgan Chase ( JPM ) and Walmart ( WMT ) are partnering to speed up payments for merchants that sell items through the retail giant's website.

The pairing will allow merchants on Walmart's ( WMT ) marketplace platform to accept and make payments, while managing cash flow using JPMorgan's ( JPM ) systems, said Lia Cao, head of embedded finance and solutions at the largest U.S. bank.

Walmart ( WMT ) sells more than 700 million items from 100,000 sellers on its marketplace platform, including beauty products, clothing, home furnishings and electronics. Marketplace sales grew 40% in the fourth quarter, it said.

Companies have been increasingly using so-called embedded finance software to offer financial services directly to customers and businesses.

More than $2 trillion of transaction volume will shift to marketplace platforms and away from traditional retailers and resellers, according to a McKinsey report.

JPMorgan ( JPM ) sees the move as a growth opportunity, Cao said. It already has over 20 clients in embedded finance partnerships and expects that to double in the next year, she said.

The partnership with Walmart ( WMT ) is only available for U.S. merchants, but the firms are in talks to expand the service into Europe and other regions, Cao said.