Nauru President Baron Divavesi Waqa read the resolution, stating that members of the parliament rejected the "one China principle" and "one country, two systems" framework and recognized Taiwan as a sovereign and independent nation. Waqa is the first foreign head of state to have publicly expressed opposition in parliament to China's "one country, two systems" framework.
Tsai flew to Nauru from Palau on Sunday to continue her eight-day visit to three of Taiwan's diplomatic allies in the Pacific, including the Marshall Islands.
On Monday morning at the Nauru government building complex, Tsai was given a grand welcome, which included a traditional dance by Nauruan students and a police parade.
At the welcome ceremony, Waqa said Taiwan and Nauru shared values of freedom and democracy and he thanked Taiwan for its assistance and support.
He also said the Nauruan government will do its utmost to support Taiwan's international participation in various international conferences and to work with Taiwan toward the goal of sustainable development.
Waqa said he hoped the two countries would continue to deepen their bilateral cooperation and consolidate their friendship.
In turn, Tsai said that before her departure for Nauru, she saw a video of Waqa speaking in anticipation of her visit and she could feel Nauru's affection for Taiwan. President Waqu is a "super good friend" of Taiwan, said Tsai, who was presented with a feather necklace and a set of commemorative stamps at the ceremony.
Meanwhile, Tsai conferred on Waqu the Order of Brilliant Jade with Grand Cordon in recognition of his contribution to promoting friendship and cooperation between their two countries.
After the ceremony, the two heads of state held closed door discussions on bilateral cooperation.
Tsai later delivered a speech in English to the Nauru parliament, after which the Taiwan-friendly resolution was passed.
Reading the resolution, Waqa said the members of the parliament welcomed Tsai's visit to the country and vowed to support and safeguard Taiwan's democratic system of governance.
The parliament respects the will of the 23 million people of Taiwan, rejects the "one China principle" and "one country, two systems" framework, opposes China's military intimidation of Taiwan and recognizes the fact that Taiwan is a sovereign and independent nation, according to the resolution.
Nauru parliamentarians also want to strengthen substantive ties with Taiwan and support its international participation in various international organizations, including the World Health Organization, the International Civil Aviation Organization, and the UN Framework Convention on Climate Change, the resolution states.