The U.S. needs to boost the number of Syrian refugees it is accepting beyond the "token increase" now planned, Democratic presidential hopeful Martin O'Malley says in a letter to President Barack Obama.

O'Malley is disappointed the U.S. is making plans to accept 10,000 Syrian refugees in the coming budget year, an increase from the 1,500 people who have been cleared to resettle in the U.S. since civil war broke out in the country.

The former Maryland governor wants the U.S. to accept 65,000 refugees from Syria by 2017. He notes that Germany is accepting 800,000 refugees this year despite having a much smaller population than the U.S.

The White House has been under pressure to do more to help address the humanitarian crisis in Europe.