WASHINGTON — Rep. Neil Abercrombie is leaving Capitol Hill as issues he cares deeply about — from the federal recognition of Native Hawaiians to the war in Afghanistan and health care reform — are coming to fruition.

But the Hawai'i Democrat has told President Obama and the national leadership of his party that he will remain in office to cast key votes, likely through the end of the year.

Those votes could include House action on health care and a bill that would grant Native Hawaiians the same federal recognition that American Indians enjoy.

One of the House committees Abercrombie sits on — natural resources — is expected to take up the historic Native Hawaiian legislation next week.

Abercrombie has scheduled a news conference tomorrow in Hawai'i, when he is expected to offer more details about when he will officially leave office.

Abercrombie, 71, has represented Hawai'i's 1st Congressional District in urban Honolulu for two decades.

As a senior member of the House Armed Services Committee, he was poised to cast important votes in the coming months on the wars in Afghanistan and Iraq. The liberal congressman opposed the war in Iraq and was deeply conflicted about the 30,000-troop surge that Obama recently announced for Afghanistan.

U.S. Sen. Daniel Inouye, D-Hawai'i, called Abercrombie's departure a surprise.

"Congressman Abercrombie's announcement is a surprise and leaves us a vote shy in the House at a time when major policy changes like health care reform, a war spending measure, the Akaka bill and others are shaping up for debate and passage," Inouye said in a statement. "However, I accept the congressman's decision and I thank him for his 10 terms of service in the U.S. Congress. I wish him well."

U.S. Rep. Mazie Hirono, D-Hawai'i, said in a statement that Abercrombie served with honor and integrity.

"Neil is respected by both Democrats and Republicans in the House, and I know that his voice will be missed by many who consider him a close friend," she said. "He has served with honor and integrity over the past two decades and has been a strong and effective advocate for Hawai'i."

Jonah Ka'auwai, the state GOP chairman, described Abercrombie's decision as a "desperate move."

"Abercrombie's resignation is simply a desperate move by the Democrat Party to steal the (2010 general) election from the front-runner Charles Djou," he said in a statement.

Honolulu City Councilman Charles Djou, a Republican, is running to replace Abercrombie in Congress, along with former congressman Ed Case and state Senate President Colleen Hanabusa, both Democrats.

"Today, furlough Friday, children are at home because of our failed Democrat-dominated politics," Ka'auwai said. "Yet Rep. Neil Abercrombie is going to force a special election and waste millions of dollars for what can only be described as his own personal political greed. How can someone who wants to hold the state's highest office possibly believe this is right for the state of Hawai'i?"