Blake Shelton_Miranda Lambert
Miranda Lambert claims that her estranged husband had cheated on her, TMZ reported late Tuesday, citing source. Reuters/Mario Anzuoni

Miranda Lambert accused her estranged husband, Blake Shelton, of cheating on her with another famous country singer, TMZ reported late Tuesday, citing sources. The news comes a day after the two announced their divorce amid cheating rumors.

Lambert, 31, claims that she was faithful to her husband during their four years of marriage, according to the sources, who called Shelton’s camp unscrupulous for accusing Lambert of cheating. TMZ reported that the “Over You” singer was angry that Shelton accused her of cheating.

An unnamed source previously told People magazine that Shelton never cheated on his wife. “Blake is just that incredibly loyal and dedicated husband," the source said, after the split. "I can guarantee you he has been faithful to that woman.”

After the news of the divorce, rumors circulated that the catalyst for the split was an extramarital affair between Lambert and country singer Chris Young.

However, Young took to Twitter to speak out on the cheating rumors after he was accused of sleeping with Lambert.

Shelton had previously admitted that he started to fall in love with Lambert when he was still married to his first wife, Kaynette Williams, who also goes by the name Kaynette Gern. In 2007, Shelton told People magazine that his marriage ended because "I just really don’t think I was ready to be a husband." At the time, rumors circulated that he and Lambert started a relationship prior to Shelton's 2006 divorce with his first wife.

Shelton and Lambert got married in 2011, and in a joint statement to the Associated Press on Monday, they revealed the end of their marriage. The couple, who do not have any children together, had reportedly signed a prenuptial agreement before their wedding.