The UN estimates there are 50
million assault rifles in Yemen.
Its population is 19 million
In a televised joint press conference on Monday, Saudi minister Prince Nayef said he hoped the agreement would help "control smuggling operations".
His Yemeni counterpart, Rashid Al-Ulaimi pledged Sanaa would do its best to prevent weapons and explosives passing undetected into the Kingdom.
Al-Ulaimi’s assurance came after unsubstantiated reports alleged that 12 of those involved in the 12 May attacks in Riyadh used weapons and explosives smuggled into the Kingdom from Yemen.
"Saudi authorities informed us that the weapons were smuggled from Yemen... the issue of smuggling and combating it need large resources and we are trying within our resources," al-Ulaimi said.
The Yemeni minister also admitted that a large number of weapons had accumulated amongst Yemeni citizens over the past years. The new agreement covers exchange of security information and extradition of suspects.
Saudi border guards stopped 381,900 illegal entries in the 11 months ending on February 2003 in the southern province of Jizan, the area border guard commander said in remarks published last Wednesday.
The vast majority of Yemenis attempting to enter Saudi are normally sent back across the 1,800-km long border between the two Arab nations.
But guards also confiscated 1.2 million rounds of ammunition and firearms, 46,700 sticks of dynamite and a large number of detonators, Major-General Saleh al-Santali told Al-Riyadh newspaper.
The arrests were made between March 2002 and February 2003.
About three million kilograms of qat, a mild narcotic chewed widely in Yemen, were also confiscated in addition to small quantities of other drugs and liquor, al-Santali added.
Thirty-six border guards were killed in the same period during operations.
The Yemeni minister also said the instability in Iraq was a major security problem for its neighbouring countries.
“Weapons available in Iraq pose a threat as it could be smuggled to many countries. I will discuss this matter with Prince Naif to solve such problems,” he said.
However, Prince Naif stated that reports of weapons smuggled into Saudi Arabia from neighbouring Iraq were still unsubstantiated, referring to the seizure of 128 kg of explosives in Al-Kharj on Saturday.
Al-Kharj is the site of a military base 80 km south of the capital. Riyadh says the explosives had been smuggled in from outside the kingdom.