Women could assume combat roles in the US army for the first time as early as this year, following a landmark decision by defense secretary Leon Panetta to lift a military ban on women serving on the frontline.

The groundbreaking move could open up hundreds of thousands of frontline positions, and could see women working in elite commando units.

One official told the Associated Press, which revealed details of the move, that military chiefs will report to the Pentagon on how to integrate women into combat roles by 15 May.

Panetta's decision was hailed as a "historic step" by one senator and could eventually open up 230,000 jobs to female military personnel. The Pentagon had previously opened around 14,500 combat positions to women in February 2012, but females were still prevented from serving in the infantry, in tank units and in commando units.

Women, although banned from serving in combat roles, have been heavily involved in the wars in Iraq and Afghanistan over the past 12 years, serving as pilots, military police, intelligence officers and other roles attached to, if not formally part of, frontline units. By last year, around 130 women had died and 800 had been wounded since the wars began.

Panetta's decision, which will be formally announced on Thursday, will go further, opening up the possibility of women serving in those roles for the first time. While some combat roles could become available for women this year, positions in special operations forces such as US navy Seals and the army's Delta Force may take longer due to lengthier assessment periods, AP reported.

Women make up 14% of the 1.4 million active military personnel, but their participation in some aspects of military life has historically been thwarted by the 1994 direct ground combat definition and assignment rule. That rule identified five areas which it said could affect women's military service – "direct ground combat, berthing and privacy, co-location, long-range reconnaissance and special operations forces, and physically demanding tasks".

The Pentagon's 2012 decision addressed two of the five concerns – allowing women to occupy intelligence and communications jobs and fill positions close to combat zones – but many positions were still male-only.

Officials will report back by mid-May on the logistics of allowing women to fill the restricted positions, while Panetta's decision gives the military services until January 2016 to seek special exceptions if they believe any positions must remain closed to women.

"This is an historic step for equality and for recognizing the role women have, and will continue to play, in the defense of our nation," said senator Patty Murray, chairwoman of the Senate veterans' affairs committee and a member of the defense appropriations subcommittee.

"From the streets of Iraqi cities to rural villages in Afghanistan, time and again women have proven capable of serving honorably and bravely.

"In fact, it's important to remember that in recent wars that lacked any true frontlines, thousands of women already spent their days in combat situations serving side-by-side with their fellow male service members."

Pressure to allow women to serve in combat positions has been growing over recent years. In November 2012, four female soldiers, with the support of the American Civil Liberties Union, announced that they were suing the Department of Defense over its restrictions on women serving in frontline warfare, the ACLU arguing that women had effectively been engaged on the combat roles in Iraq and Afghanistan given the nature of those two wars and the changing notion of the 'frontline'.

The ACLU cautiously welcomed Panetta's decision on Wednesday.

"We are thrilled to hear Secretary Panetta's announcement today, recognizing that qualified women will have the same chance to distinguish themselves in combat as their brothers-in-arms, which they actually already have been doing with valor and distinction," said Ariela Migdal, senior staff attorney with the ACLU Women's Rights Project.

"But we welcome this statement with cautious optimism, as we hope that it will be implemented fairly and quickly so that servicewomen can receive the same recognition for their service as their male counterparts."

Role call

UK

Women are banned from close-combat roles. They are allowed to support frontline operations in areas such as logistics, artillery and engineering but are excluded from joining the infantry or serving in small tactical combat arms teams which require close contact with or killing enemy face-to-face. The Ministry of Defence reviewed the policy in 2010 and concluded that women were physically and psychologically capable of the job but the impact of having mixed-gender teams were unknown and could have "far-reaching and grave consequences".

Canada

Women are permitted to take on all military roles including close combat. The policy was adopted in 1989 following a decision by the Canadian Human Rights Commission Tribunal that females should be fully integrated into all roles except service on submarines, although this restriction was later removed. In May 2006, Captain Nichola Goddard became the first woman in Canadian history to be killed while serving in a direct combat role, against the Taliban.

Germany

Women have been allowed to serve in close combat roles since 2001 following a ruling by the European Court of Justice that preventing females from occupying such positions was against gender equality principles. By 2009, the number of women in the armed forces was three times that in 2001, with an estimated 800 in combat units.

Australia

Women have been permitted in all frontline combat roles since 2011. Before, women were eligible for around 93% of roles, but were excluded from the special forces, infantry and some army artillery posts.

Cass Jones