SoftBank is willing to re-engage Charter Communications on a deal if the cable giant's management indicates interest, sources told CNBC.

During the summer the Japanese conglomerate had worked on a move to acquire Charter for $540 a share in cash and stock, the sources said. SoftBank would have contributed Sprint shares to the new company at roughly $10 a share, they said.

Charter shares traded around $402 as recently as September but have since fallen. They opened for trading at $338 on Monday.

SoftBank's founder Masayoshi Son had been trying to put together a deal to combine Sprint and T-Mobile but talks were drawn out as the two sides battle over governance and control issues. Those talks officially ended Saturday as both companies said a deal could not be reached.

But Son has also mulled a deal with Charter, which is 27 percent owned by Liberty Media and its chairman, John Malone. Liberty and the Newhouse family together control almost 50 percent of Charter's equity. Liberty was interested in the SoftBank offer while Charter's management was not, the sources told CNBC.

Liberty's broadband operation would have rolled into the new company, the sources said.