Kushner Cos, the realty company once headed by President Donald Trump's son-in-law, said on Tuesday it is reassessing how to finance the redevelopment of its flagship New York City property after failed talks with a former Qatari prime minister.

Talks that began more than two years ago to invest in 666 Fifth Avenue, located in the heart of Manhattan, with Qatar's Sheikh Hamad bin Jassim al-Thani were "recently terminated," a Kushner spokesman, James Yolles, said in a statement to Reuters.

Kushner Cos "is currently reassessing the financing structure of the overall project. The company remains in active discussions with a number of potential investors around the property's redevelopment," Yolles said.

Sheikh Hamad agreed to invest $500 million on condition that the company, recently headed by Jared Kushner, Trump's son-in-law and now one of his senior advisers, obtain the rest of a multi-billion-dollar refinancing elsewhere, The Intercept publication reported on Monday.

Jared, who is married to Trump's daughter Ivanka, sold his interests in the company to a family trust in January.

Sheikh Hamad was Qatar's prime minister from 2007 to 2013 and was foreign minister for more than 20 years.

President Trump in early June accused Qatar of being a "high level" sponsor of terrorism, days after four Arab states cut ties with the Gulf nation over its alleged support of terrorism.

Kushner Cos in March said it ended talks with China's Anbang Insurance Group to redevelop the 39-story marquee property it bought in 2006 for $1.8 billion, at the time a record for a Manhattan office building.

Talks had centered on Anbang providing as much as half of $2.5 billion in equity in a plan that called for stripping the building down to its steel columns and adding about 40 floors, according to media reports. A $1.2 billion loan used to buy the property was later refinanced and comes due in February 2019.

The company also said in March that advanced talks were ongoing with other investors to redevelop the tower, valued for its proximity to St. Patrick's Cathedral and Rockefeller Center.

Kushner Cos has a joint venture in the 60-year-old tower with Vornado Realty Trust, a major city property owner.

(Reporting by Herbert Lash; Editing by Daniel Bases and Leslie Adler)