Maccabi Tel Aviv increase bid for U.S. defender Steve Birnbaum - sources

Video via MLS: Why DC United are feeling the Birn(baum) (1:54)

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Israeli giant Maccabi Tel Aviv has lodged an improved $800,000 bid for United States defender Steve Birnbaum, but D.C. United is refusing to sell the center-back, sources told ESPN FC.

Club sources said on Friday that D.C. United is not currently entertaining offers for the 25-year-old and is "comfortable" letting Birnbaum play out the rest of his contract, which runs until January 2018.

D.C. United would still hold Birnbaum's MLS rights at that stage if the contract expires.

One source close to Birnbaum, however, says the national team defender would want the move to Maccabi if he isn't offered a new deal with D.C. United.

Although Birnbaum is cap-tied to the United States in terms of his international career, Maccabi could try to help Birnbaum, who is Jewish, secure an Israeli passport so the club could employ him as a national without counting against the league's foreigner limit.

Birnbaum is still playing on his rookie-scale contract and, according to sources, has been seeking a new deal since November.

MLS rules allow Birnbaum to sign a pre-contract with a club abroad in July 2017, six months before his current D.C. United deal expires.