MILAN - Italy's three main rightist parties on Sunday vowed to present a united front in a fresh round of talks on forming a new government next week, defying attempts by the anti-establishment 5-Star Movement to divide them in coalition negotiations.

Following last month's inconclusive election, President Sergio Mattarella wrapped up an initial round of consultations on Thursday and promised to meet party leaders again soon to try to break the gridlock and put together a new government.

The March 4 vote saw the anti-establishment 5-Star Movement emerge as the largest single party, while a rightist alliance, including the League, Brothers of Italy and Silvio Berlusconi's Forza Italia (Go Italy!) group won the biggest bloc of seats.

The leaders of the three rightist parties - the League's Matteo Salvini, Berlusconi and Brothers of Italy's Giorgia Meloni - met on Sunday to agree on a common message to present to Mattarella.

"Almost 40 percent of Italians have chosen to give their trust to the centre-right parties, which today, without a doubt, have the task of forming a government," the three said in a joint statement following a meeting at Berlusconi's palatial residence at Arcore near Milan.

The centre-right coalition will insist on naming the next prime minister and that the main parts of an election programme agreed before the ballot be respected, including proposed tax cuts, job incentives and a stop to illegal immigration.