Tensions between the ruling Hamas faction and once-dominant Fatah flared after Abbas this month called for early elections, a move Hamas called a "coup". Hamas, sworn to destroy Israel, beat Fatah in a January parliamentary vote.
Hamad said: "Haniya has welcomed the invitation. Arrangements are under way to agree on the date."
"The Jordanian prime minister has extended an official invitation from his majesty King Abdullah to Prime Minister Haniya to visit Jordan and to meet President Abu Mazen [Abbas] to discuss the latest developments and the issues of difference," Hamad said.
Hamad told Al Jazeera that the invitation demonstrated a "thawing relations between Hamas and Jordan".
"Jordan now is playing an important role in bringing the Palestinian factions together." he said.
Jordan has openly expressed support for Abbas and a renewal of Israeli-Palestinian peace talks, but has traditionally not had good ties with Hamas.
A Jordinian government spokesman said: "This is a follow-on his majesty's initiative to exert all efforts to reinvigorate the peace process and solidify Palestinian national unity."
"Jordan now is playing an important role in bringing the Palestinian factions together"
In April, Jordan cancelled an invitation to Mahmoud al-Zahar, the Palestinian foreign minister and a Hamas leader, after Amman said it had found weapons smuggled in from Syria and hidden by Hamas activists
Hamas denied involvement.
In November, Jordan's state prosecutor charged three Hamas fighters with plotting to carry out attacks against the country.