Vornado Realty renewed and increased an unsecured revolving line of credit Thursday. Vornado Realty, which is a unit of Vornado Realty Trust (VNO), increased the credit facility to $1.25 billion from $1 billion. The renewed credit line matures in four years and has a one-year extension option. Vornado said Thursday it plans to extend a second $1.6 billion credit line once it matures in September 2012. The Paramus, N.J.-based firm now has credit facilities totaling nearly $2.9 billion, with $100 million outstanding. The company wasn’t immediately available to comment on the increased credit lines, but a recent article by Reuters suggests Vornado may be entering the market for commercial mortgage-backed securities. Reuters reported Vornado is looking for a $600 million to $700 million loan, which would be used to refinance an unidentified building, according to Vornado chief executive officer Michael Fascitelli. Vornado Realty Trust is a real estate investment trust and one of the largest owners and managers of commercial real estate in the U.S. The company’s portfolio currently holds properties totaling more than 100 million square feet. Write to Christine Ricciardi. Follow her on Twitter @HWnewbieCR.