Trump lashes out at own party on social media

United States presidential candidate Donald Trump has stepped up his attacks on House speaker and fellow Republican Paul Ryan as dissension within the party rises.

Ông Paul Ryan, người hứng chịu các vụ tấn công của ông Trump Source: AAP

Mr Trump's attacks come a day after Mr Ryan, the top Republican in Congress, refused to defend him or campaign for him.

Facing criticism over sexually aggressive comments that surfaced on the weekend, the Republican nominee has seen his support among many Republican politicians slide.

It all comes less than a month before the national election.