Two Kuwaiti soldiers are to stand trial accused of plotting attacks against US troops stationed in the country.
US troops heading to Iraq are often trained in Kuwait
A number of other Kuwaiti soldiers were questioned over alleged plots but later released, Kuwait's army chief said.
The US embassy in Kuwait warned last month of "credible information" that militants were planning attacks.
About 25,000 US troops are stationed in Kuwait, which was a launch pad for the Iraq war in 2003, but some anti-western feeling is growing in Kuwait.
Kuwaiti security services were reported to have questioned up to eight men over alleged involvement in plots to attack US troops while they trained in the Kuwaiti desert.
But after investigations concluded just two of the suspects were formally charged.
The two will face trial in a military court, Kuwaiti Chief of Staff Yousef Abdelrazzak al-Mulla said.
On Wednesday Kuwait's Foreign Minister, Sheikh Mohammad al-Salem al-Sabah, urged Kuwaitis to be on the alert against what he called "evil intentions against their country".
Kuwait has been a staunch US ally since it was freed from Iraqi rule during the 1991 Gulf War.
Many Kuwaitis remain well disposed towards the US, but anti-western sentiment in the country has grown since the Iraq war.
Kuwait stepped up security following the US embassy warning, stationing armed military and police vehicles around Western embassies, oil facilities and also on major street junctions.
A group of 20 Kuwaiti men are already being tried for plotting to attack US forces in Iraq and Kuwait.