President Donald Trump's son-in-law and senior adviser Jared Kushner said that the Palestinians aren't yet able to govern themselves and declined to promise them an independent state in the White House's long-awaited Mideast peace plan.

"The hope is that they over time will become capable of governing," Kushner said in an interview with Axios on HBO that aired on Sunday.

Kushner is leading a White House effort to draft a peace proposal for the Israelis and Palestinians. The effort faltered after Trump announced in 2017 he would move the U.S. embassy to Jerusalem. The Palestinians have said they will boycott an economic conference in Bahrain this month that Kushner arranged as a first step in the peace plan.

In the interview, Kushner repeatedly criticized Palestinian leaders, drawing a distinction between their drive for an independent state and what he said was the Palestinian people's desire to live in peace and prosperity. The interview represents some of his most extensive public remarks since joining his father-in-law's administration.

"There are some things the current Palestinian government has done well, and there are some things that are lacking," Kushner said. "And I do think that in order for the area to be investable, for investors to want to come in and invest in different industry and infrastructure and create jobs, you do need to have a fair judicial system, you need to have freedom of press, freedom of expression, tolerance for all religions." Many U.S. allies in the region, such as Saudi Arabia and Egypt, reject those democratic principles.

Kushner would not commit to U.S. support for an independent Palestinian state and said there's a "high bar" for Palestinians to be free from interference in their affairs by the Israeli government and military.