Leading politicians, military officers and diplomats from around the world gather in Munich on Friday for a security conference that will be dominated by the wars in Israel and Ukraine as well as fears over the US commitment to defending its allies.

German Chancellor Olaf Scholz, US Vice President Kamala Harris and Ukrainian President Volodymyr Zelensky are among top officials attending the Munich Security Conference (MSC), an annual global gathering focused on defence and diplomacy.

Israel's President Isaac Herzog and Palestinian Prime Minister Mohammad Shtayyeh are also expected to attend the conference, which begins on Friday and runs until Sunday at the luxury Bayerischer Hof hotel in the southern German city.

The conference takes place as the war in the Gaza Strip between Israel and the Palestinian militant group Hamas, in which more than 28,000 Palestinians and about 1,430 Israelis have been killed, enters its fifth month with no end in sight.

It also takes place shortly before Russia's full-scale invasion of Ukraine enters its third year.

Both wars have ignited fears that will likely be addressed at Munich about possible regional spillover.

"The world has become more dangerous," Jens Stoltenberg, Secretary-General of the NATO Western defence alliance told Reuters on Wednesday.

British Foreign Secretary David Cameron said officials from European countries that help to fund the occupied Palestinian territories and key Arab and Gulf states would meet on the sidelines of the Munich event to start discussing the future for Israel and the Palestinian people after a potential ceasefire.

US Secretary of State Antony Blinken is also expected to join.

"There are lots of things we need to start talking about now," Cameron said in remarks to Britain's House of Lords. "Whether it's about this question of how you offer a political horizon to people in the Palestinian territories, or indeed, how we deal with Israel's very real security concerns."

Israeli Foreign Minister Israel Katz said he would set foot on German soil for the first time to give a keynote speech at the conference, after refraining from doing so as he grew up in a family of Holocaust survivors.

""I will do everything for Israel's security, securing our future and returning the hostages," he said.

UKRAINE AID BILL FACES HURDLES

Zelenskiy is expected to plead for more support for Ukraine as the US House of Representatives stalls a multi-billion dollar military aid package for the country.

"The stakes couldn't be higher," said one senior State Department official, saying the delay was already being felt on the battlefield. "Our support is absolutely essential in achieving the objectives Ukraine has."

European and US officials are increasingly warning of the risk Russian President Vladimir Putin could attack other countries if his military operation in Ukraine is successful.

"It is clear Putin will not stop at Ukraine," a second US State Department official said.

No Russian officials were invited to the MSC, for the second year in a row, as they did not seem interested in meaningful dialogue, organisers said.

TRUMP CASTS SHADOW

The event comes as the US commitment to defending its allies more broadly is in doubt as the prospect of a re-election of former President Donald Trump looms.

Such worries have re-ignited a push in Europe for more strategic autonomy. Until recently the idea was championed by only a handful of countries, in particular France, but is gaining traction and will likely be addressed at the security gathering.

Trump, the front-runner for the Republican presidential nomination, suggested last Saturday he would not defend NATO allies who failed to spend enough on defence, prompting consternation in Europe.

Harris is scheduled on Friday to deliver what aides have billed as a major speech on "the importance of fulfilling the US role of global leadership" before meeting with US lawmakers, Zelenskiy and Scholz.

Harris is also likely to be closely watched for her ability to lead after a Department of Justice special counsel report last week described US President Joe Biden, 81, as an elderly man with a "poor memory." Trump is 77.

Other big international issues will also feature at the conference, such as conflicts in the Horn of Africa increasing food insecurity and displacing millions, and relations between the West and China.