Guaido said in a statement that his representatives "will talk with both the Norwegian government and with representatives of the regime" after the two sides traveled separately to Oslo last week to meet with the leaders of the Norwegian mediation effort.
Envoys representing the two sides will "continue a process facilitated by Norway," the Scandinavian country's Foreign Minister Ine Eriksen Soreid said.
The mediation bid comes after a months-long power struggle between National Assembly leader Guaido and the socialist president, with sometimes deadly street clashes. US-backed Guaido is recognized by dozens of countries as interim president after dismissing Maduro's presidency as "illegitimate" following his re-election last year in polls widely dismissed as rigged.
Maduro has been shunned by much of the international community for presiding over the country's economic collapse, which has led to shortages of basic goods -- forcing millions to flee -- as well as brutally suppressing dissent. He retains the backing of major creditors Russia, China and Cuba, as well as the powerful military.
Guaido told supporters on Saturday that he is cautious about the Oslo talks since they are unpopular with the opposition base that has spent months in the streets trying to push Maduro out. Guaido said there had been no "negotiation" in the Norway talks, while any deal should include mediation leading to Maduro's departure and new elections being scheduled.
"We are going to insist," he said, "because today by combining all our strategies, using all the tools we have, we are going to get to that final step," Guaido said, referring to street protests and multiple levels of diplomacy.
Guaido tried to incite a military uprising against Maduro on April 30 but only about 30 members of the armed forces joined him.
The socialist regime has since ramped up pressure on Guaido's allies and supporters, charging 10 lawmakers with treason. The pro-government Constituent Assembly recently stripped 14 opposition lawmakers of their legislative immunity over their support for the failed uprising.