Bolivian President Evo Morales and natives who have marched all the way from the Amazon to protect their ancestral homeland from a government road project were at loggerheads early Friday over talks.

After a chilly night camped out in front of the presidential palace, native leaders on Thursday apparently refused an invitation to meet with Morales at the vice president's office to discuss their grievances.

"I lament that they have not shown up," Morales told reporters, explaining that the palace was being remodeled and that the only place large enough to meet with such a large group was there.

Native leader Fernando Vargas had insisted on meeting with 100 of his supporters in the presidential palace, "where Morales carries out his duties."

But the president said the meeting could only be held at his office if the number of native negotiators was reduced to 20.

Late Thursday, police fired tear gas at a group of protesters who tried to advance beyond a security fence outside the palace, and two police were treated for minor injuries, Interior Minister Wilfredo Chavez told local television.

He denied there was any order to disperse the protestors, however, and said the police had responded after being attacked by drunk people.

Nearly 2,000 indigenous people made a triumphant entry into La Paz on Wednesday after a two-month march from the Amazon against the plans for a road through the pristine Isiboro Secure National Park and Indigenous Territory.

The marchers, who set out in August and trekked 600 kilometers (370 miles) from the lowlands high into the plateaus of the Andes, were met as heroes as they entered the capital and made their way to the presidential palace.

About 50,000 people from three different native groups live in the remote territory in the humid Amazon lowlands. They fear that a road will destroy their land and bring in a flood of landless farmers from the highlands.

Earlier this month, Morales agreed to postpone construction of the roadway, a delay Bolivia's legislature later approved.

But the protesters are seeking assurances that the project -- or at least the Amazon portion of it -- will be scuttled for good.

"If work begins, we will fight in the forest until death," said indigenous leader Adolfo Chavez.

The standoff poses a major challenge to Morales, a leftist elected five years ago as Bolivia's first indigenous president, who now finds himself entangled in a messy row over natives' rights and economic development.

The marchers, including women, children and elderly people, endured heavy rains, cold temperatures, mountainous terrain and police brutality during their two-month long journey to La Paz.

A police crackdown that left 74 people injured in late September triggered widespread anger, a general strike and the resignations of several top government officials, including two ministers.

Work on the highway, which was supposed to be operational in 2014, began in June, although not on the segment running through the protected park.