Mexico Trump
Mexico Trump

WASHINGTON - U.S. President Donald Trump said Wednesday the design of a wall to stem the flow of illegal immigrants into the U.S. from Mexico is underway.

“The wall is getting designed right now. We will have a wall. It will be a great wall and it will do a lot of — will be a big help,” Trump said without offering specifics during a speech in Washington before the Major Cities Chiefs Police Association.

Trump repeated his vow to build a wall along the U.S. border with Mexico as a way to “stop the drugs from pouring into our country” and cited Israel as a country that has successfully erected walls along its borders.

WATCH: Trump discusses U.S.-Mexico wall

“Do walls work? Just ask Israel. They work if it's properly done,” Trump said.

Israel began building a system of barriers in 2002, during the peak of the second Palestinian uprising that saw suicide bombers detonating explosives in public places in Israeli cities.

After a series of terrorist attacks, Israel built a barrier along and inside the West Bank that was designed to regulate the entrance of Palestinians into Israel. Israel has also erected fences along the borders it shares with Egypt and Lebanon, and along its boundary with the Gaza Strip.

There has been a significant drop in terrorist attacks by West Bank Palestinians since March 2002. And while Israeli security officials credit the barriers for the decline, attacks continued to drop when the second Palestinian uprising weakened in 2004 and the militant group Hamas imposed a moratorium on suicide bombings.

The Israeli military also regularly arrests suspected militants on the other side of the West Bank barrier and the country continues to benefit from security support from the Western-supported Palestinian Authority.

Last week, Israeli Prime Minister Benjamin Netanyahu tweeted in support of Trump's proposed wall.

“President Trump is right. I built a wall along Israel's southern border. It stopped illegal immigration. Great success. Great idea,” Netanyahu wrote.

An Israeli company that helped construct Israel's West Bank barrier is reportedly seeking to build the wall along the U.S.-Mexican border for the Trump administration.

Magal Security Systems described its high-tech border fence at a January 31 border security conference in Northern Virginia that was attended by officials from the U.S. Department of Homeland Security, according to Bloomberg News.  

Pope John Francis, meanwhile, reiterated his opposition Wednesday to Trump's proposed wall. During his weekly address at the Vatican, the pope said the world should "build bridges" and not “create walls.”