PRISTINA, Kosovo - Secretary of State John Kerry delivered a message of support for Kosovo's government Wednesday, urging it to stick to accords that would provide ethnic Serbs greater autonomy and demarcate the young nation's border with Montenegro. He decried efforts by opposition lawmakers to scuttle both deals by intimidation.

Kerry also sought tougher action by the government to prevent Kosovars from joining the flood of foreign fighters joining the Islamic State in Iraq and Syria. The Muslim-majority country, born out of Yugoslavia's violent breakup in the 1990s, has seen a greater percentage of its citizens fight for ISIS than any country in Europe.

Stopping in Pristina for less than two hours after leaving a NATO meeting in Brussels, Kerry backed Kosovo's efforts toward closer cooperation with its neighbors and said the twin agreements would not threaten the country's security or independence. "We have invested far too much, ourselves, together, in Kosovo's future to put it at risk," he said after meeting Prime Minister Isa Mustafa and other senior officials.

The U.S. and its NATO allies carried out a bombing campaign between March and June 1999, designed to force Serbian forces out of Kosovo and get Belgrade to accept the deployment of a NATO peacekeeping force.

The accords have plunged Kosovo into political crisis. Earlier this week, opposition lawmakers broke up a parliamentary session with tear gas, saying they would block proceedings until the government renounced its intention to give Serb communities greater powers and to define its 50-mile-long eastern boundary with Montenegro. The opposition has regularly disrupted parliament with pepper spray, whistles, and water bottles as well, and is vowing street protests.

Kosovo and Serbia have been holding European Union-mediated talks as Serbia still rejects Kosovo's 2008 declaration of independence.

Kerry's words carry weight in Kosovo, a bastion of pro-American sentiment. Since Kosovo's independence, the U.S. has provided $950 million in aid. Despite not venturing beyond the airport, Kerry was greeted with welcome banners and U.S. flags.