With time running out before automatic federal budget cuts hit the commonwealth disproportionately hard, Virginia politicians are ramping up their efforts to head off sequestration.

Suffolk’s voice in the U.S. House of Representatives is among a bipartisan delegation of Virginia congressmen that has sent President Barack Obama a letter showing “unified support” for immediate action ahead of the March 1 so-called fiscal cliff deadline.

Without agreement between lawmakers on either spending less or taxing more — or a combination — by then, $109 billion of indiscriminate cuts will hit military and domestic spending.

Randy Forbes signed the letter, sent to the President Friday, alongside fellow Republicans, Reps. Rob Wittman, Scott Rigell and Frank Wolf, and Democrats, Sens. Mark Warner and Tim Kaine and Reps. Robert Scott, Jim Moran and Gerry Connolly.

“As a bipartisan delegation of Virginia lawmakers representing wide-ranging interests and viewpoints, we write to show unified support for immediate action to avert the devastating impacts of sequestration,” the letter states.

Virginia’s “long history of contribution to national defense and to the federal government,” it continues, “will bear a disproportionate amount of the pain.”

The letter cites a George Mason University study showing that almost 10 percent of sequestration job losses would occur in Virginia.

“Of these 207,571 Virginia jobs, 136,191 will be lost as a result of cuts to defense, 71,380 job losses will result from reductions in non-defense spending,” it reads.

The sequester would also slash $20.8 billion in gross state product, the letter reads, and “ripple to all parts of our state economy and lead to a hollow military force and a government unable to adequately respond to the needs of its citizens.

“We stand ready to work hand-in-hand to negotiate an agreement to avert these cuts that threaten grave consequences for the commonwealth, our federal government, and our national security.”

The letter was also sent to House Speaker John Boehner and Senate Majority Leader Harry Reid.

Meanwhile, Gov. Bob McDonnell on Monday sent another letter urging action to stop sequestration to President Obama and Virginia’s congressional delegation.

While the automatic cuts were designed to force a comprise between lawmakers by being so onerous as to be unthinkable, “inaction by you and Congress now leaves states and localities to adjust to the looming threat of this haphazard idea,” McDonnell wrote.

McDonnell calls for “immediate attention to address the potential devastation,” which he fears would push Virginia, which has achieved the lowest unemployment rate in the nation’s Southeast, back into recession.

“In order to mitigate the negative impacts as effectively and as quickly as possible, and to ensure a continued robust economy in Virginia, it is critical that you lead Mr. President, and that you work with Congress to come together in the best interests of the nation, and produce the necessary legislation to avoid the disastrous effects of this ill-conceived policy,” he wrote.