Bitcoin is holding above the $81,000 mark after reaching a two-and-a-half-week high overnight.

The flagship cryptocurrency continued its rebound on Monday, adding 0.9% to $81,938 after an uplift of nearly 6% last week. Investors shrugged off two potential hurdles--a failure to pass the Clarity Act, as well as the Federal Reserve's quarter-point interest-rate hike--to finish the week higher.

It is now up over 27% since Aug. 19 and is holding firmly above the $80,000 level that has proved a stubborn cap in recent weeks.

"The move back above $81,000 came even after tighter monetary policy, showing that institutional demand is currently absorbing part of the pressure from higher interest rates," wrote Zaye Capital Markets analyst Naeem Aslam in a note.

Bitcoin is supported by stronger exchange-traded fund inflows, positive regulatory developments and investors closing earlier bets against the cryptocurrency, according to Aslam.

Investors are looking ahead to the planned summit between U.S. President Trump and Chinese President Xi Jinping on Thursday. A truce in the tariff war is due to expire on Nov. 10, and any progress made to ease trade tensions could boost sentiment for risk assets including cryptocurrencies.