Pope Francis on Friday referred to himself as a "bridge builder" and called for more intense dialogue with Muslims and countries that have no official relations with the Vatican.
The Pope spoke to ambassadors from 180 countries accredited with the Holy See.
"It is not possible to establish true links with God, while ignoring other people," said Francis. "Hence it is important to intensify dialogue among the various religions, and I am thinking particularly of dialogue with Islam."
Relations between Islam and the Vatican became strained for a while during Pope Benedict XVI's papacy.
In 2006, Benedict gave a speech that included a quote from a Byzantine emperor who accused the Islamic prophet Muhammad of doing only evil deeds. The speech enraged Muslims around the world, leading to riots and the burning of churches.
Two years later, Benedict called for better protection of Christians in Cairo following a church bombing. Al Azhar University, considered the authority in Islamic education, froze relations with the Holy See.
Relations may be opening up with Pope Francis at the helm of the Roman Catholic Church. The Vatican reported that the head of the Egyptian university congratulated Pope Francis on his inauguration.
On Friday, the Pope expressed his appreciation that many civil and religious leaders from the Islamic world attended his installation Mass.
Speaking in the Sala Regia of the Vatican, Francis was optimistic that dialogue would "help to build bridges connecting all people, in such a way that everyone can see in the other not an enemy, not a rival, but a brother or sister to be welcomed and embraced!"
A son of Italian immigrants, the pontiff said "dialogue between places and cultures a great distance apart matter greatly" to him.
Pope Francis also explained that he chose the papal name after Francis of Assisi because of his love for the poor and his work for peace.
"Francis of Assisi tells us we should work to build peace. But there is no true peace without truth! There cannot be true peace if everyone is his own criterion, if everyone can always claim exclusively his own rights, without at the same time caring for the good of others, of everyone, on the basis of the nature that unites every human being on this earth."
Francis urged the diplomatic representatives present to renew their commitment to "fighting poverty, both material and spiritual, building peace and constructing bridges."
The pontiff also echoed a call made during his inaugural address for non-believers to work with people of faith to help the poor and protect the environment.
At the same time of engaging in interreligious dialogue, "it is important to intensify outreach to non-believers," said Francis, "so that the differences which divide and hurt us may never prevail, but rather the desire to build true links of friendship between all peoples, despite their diversity."