US Vice President Joe Biden is seriously considering to challenge front-runner Hillary Clinton for the Democratic nomination for president, reports say.

The New York Times reported on Saturday that Biden has already begun “to actively explore a possible presidential campaign,” after mainly putting off such considerations during his son's illness and following his tragic death in May.

Biden's associates have resumed discussions about a 2016 presidential run. Their recent communications with Democratic donors and organizers have led to speculations that Biden will finally take on Clinton.

But people close to the vice president say he has yet to make a public commitment to running for the presidency, and not yet asked his staff to plan for a potential campaign.

According to a New York Times article by veteran journalist Maureen Dowd published on Saturday, when Biden’s son, Beau, realized that he would not survive brain cancer, he talked to his father and urged him to challenge Clinton.

According to Dowd, the ailing son argued that Biden would be a better president than Clinton.

Dowd wrote that the vice president is “talking to friends, family and donors about jumping in” following his son’s passing.

Following the death of Beau, supporters offered condolences to Biden and called on him to run for president.

Seventeen Republicans are seeking their party’s nomination for president but only a few are considered serious contenders.

Democrat front-runner Clinton is competing against only three Democrats and one independent senator, Bernie Sanders, for the Democratic Party's nomination. Only Sanders is considered at all competitive in the early primaries, even as he operates with far less money than the former secretary of state.