Washington DC - President Donald Trump's acting Federal Emergency Management Agency Director David Richardson has resigned after facing criticism for going MIA during hurricane season.

Richardson exited the position of acting FEMA administrator after only six months in the role, amid accusations that he was inaccessible to agency staff during deadly flash flooding in Texas in early July.

The FEMA director had been on vacation with his two sons at the time, resulting in significant delays in the deployment of crucial emergency aid that had required his sign-off.

CNN reports that there were already talks behind the scenes to oust Richardson from the position before he submitted his resignation letter to the Department of Homeland Security on Monday.

The DHS will replace Richardson, who entered the position in early May with no prior emergency aid experience, with FEMA's newly appointed chief of staff, Karen Evans, who will take over as director on December 1.

"FEMA and the DHS extend their sincere appreciation to the senior official performing the duties of the administrator, David Richardson, for his dedicated service and wish him continued success in his return to the private sector," a DHS spokesperson said in a statement.

Richardson defended his tenure at FEMA in a statement on Monday on the basis that he had taken the position mere weeks before the beginning of hurricane season, while many others had turned down the post.

"I agreed to be the acting administrator through hurricane season when others wouldn't," Richardson said. "Hurricane season ends on 1 December."

"Since the danger has largely passed, I can now leave for other opportunities," he continued. "Many were asked. One raised his hand and said, 'I'll do it.'"