WASHINGTON—The Obama administration and European governments are stepping up efforts to revive Arab-Israeli peace talks, saying they have little time to head off a Palestinian drive to seek United Nations recognition as a state.

The White House this week dispatched its top Middle East negotiators, Dennis Ross and David Hale, to the region to try to gain Israeli and Palestinian agreement to resume negotiations based on parameters President Barack Obama laid out last month, according to U.S. and Israeli officials.

Mr. Obama called for utilizing Israel's borders before the 1967 Six-Day War as the baseline for new talks, while recognizing the need for some territorial adjustments—a plan Israeli Prime Minister Benjamin Netanyahu has rejected.

The European Union's foreign-policy chief, Catherine Ashton, meanwhile, arrives in Jerusalem Friday to push an even more aggressive plan, according to European officials.

The EU wants the quartet of international powers promoting Mideast peace—the U.S., Russia, U.N. and EU—to present the Israelis and Palestinians with a formal "framework" for future talks, which would incorporate Mr. Obama's position on the 1967 lines and other terms. European countries, led by France, are also seeking to host in the coming weeks an international conference to resume the peace process.

"I believe what is needed now is a clear signal to the parties, and a reference framework that should enable them to return to the negotiating table," Ms. Ashton wrote Secretary of State Hillary Clinton last week in a letter viewed by The Wall Street Journal.

This intensified diplomatic activity is being driven by mounting concerns in Washington and Europe that Palestinian President Mahmoud Abbas's push for a U.N. General Assembly vote on a state embodying the West Bank, Gaza and East Jerusalem set for September could have far-reaching implications for Mideast stability. The Palestinians currently have the status of U.N. observers without voting rights but are hoping that a September vote would give them status as a sovereign member.

Such a vote would have only limited legal implications for the Palestinians, according to Western and Arab diplomats, and would likely pass by a wide margin. But there are concerns a yes vote could raise expectations among Palestinians, hopes that might quickly succumb to violent discontent among Arab groups if the actual creation of an independent state remains elusive.

Already in recent weeks, protesters in Lebanon, Syria and the Palestinian territories have sought to cross their borders with Israel to show support for a Palestinian state. Such civil disobedience could swell after September, said these diplomats, particularly in light of the broader protest movements that have swept the Middle East and North Africa since December.

"We need to contribute to a calming of a volatile situation that promises to be even more so as the year progresses," Ms. Ashton said in her letter to Mrs. Clinton.

In recent days, Mr. Obama has sought to build public support for his position on the peace process, which has been strongly criticized by both Republicans and Democrats.

On June 10, the White House's senior director for the Middle East, Steven Simon, told Jewish-American leaders that the international community had roughly a month to convince Mr. Abbas to give up his campaign at the U.N., according to participants in the conference call. Mr. Simon said the Palestinians appeared "forthcoming" in responding to Mr. Obama's calls for a resumption of negotiations based on the 1967 lines, but that Israel needed more convincing. Mr. Netanyahu has called Israel's borders before the Six-Day War "indefensible." In 2004, President George W. Bush signed a letter stating that the U.S. recognized some Jewish settlements in the West Bank would remain part of Israel as part of a broader peace agreement. Israeli officials have also said they shouldn't be forced to give up bargaining chips ahead of any negotiations.

Israeli officials in recent days said the biggest issue preventing the resumption of peace talks is the political alliance Mr. Abbas forged last month with the militant Palestinian organization, Hamas, which both the U.S. and EU designate as a terrorist organization. Mr. Netanyahu has repeatedly stated that he wouldn't sit down with Mr. Abbas as long as the Palestinian leader is aligned with Hamas.Palestinian officials also offered limited optimism Thursday that peace talks would resume soon. They praised the parameters Mr. Obama laid down. But they stressed that Israel would also have to take other steps to underpin the peace process, such as halting any new construction in the West Bank and East Jerusalem, something Mr. Netanyahu has refused to do.

"Israel wants this process to succeed, but there are obstacles: first and foremost…there is this pact," said an Israeli official Thursday.

"I look at the debate in Israel and the reaction of the Israeli government, and I find it difficult to be optimistic about a resumption of talks," said Ghassan Khatib, a spokesman for the Palestinian government.