A tired but healthy-looking Sudanese President Omar al-Bashir appeared on television Thursday after a minor operation, calling Israel "enemy number one" in a return to his typical fiery rhetoric.

Bashir, 68, spoke standing at a lectern for about 15 minutes in what government-owned Blue Nile TV said was a broadcast recorded earlier in the day at Sudan's embassy in Riyadh, Saudi Arabia.

The president left hospital in the Saudi kingdom on Wednesday and was recovering there after a "successful small surgery," his second in less than four months. The operation followed a normal medical check connected to an infection in his vocal cords, official media reported.

Known for his sharp-tongued public speeches, Bashir had been relatively quiet in recent weeks, making his fewer orations more restrained.

"Israel is our enemy, our number one enemy, and we will continue calling Israel our enemy," he said in a voice which sounded normal.

The comments were his first about Israel since Khartoum accused the Jewish state of sending four radar-evading aircraft to strike the Yarmouk military factory in the heart of Khartoum at midnight on October 23.

Israel refused all comment on Khartoum's accusation.

But Israeli officials have expressed concern about arms smuggling through Sudan and have long accused Sudan of serving as a support base for militants of the Islamist Hamas movement which rules Gaza.

"After the Yarmouk incident many people were angry and asked, 'Why did this happen?', said Bashir, who smiled occasionally during his address.

To prevent another attack Sudan has two choices, he said. One is to normalise relations with Israel, which he vowed would never happen.

"The second choice is to have a technology that allows us to do an identical attack against Israel. I cannot say this is impossible. We are trying to have this technology."

After the Yarmouk compound exploded and burst into flames, speculation followed that Iranian weapons were stored or manufactured there.

Sudan denied Iran had any involvement in the factory.

Bashir also touched on the contested border region of Abyei.

The African Union's Peace and Security Council has given Sudan and South Sudan until December 5 to agree on the final status of Abyei, which Sudanese troops withdrew from in May to end a year-long occupation.

Ethiopian peacekeepers now control the area.

Abyei was to hold a referendum in January 2011 on whether it belonged with the north or South, but disagreement on who could vote stalled the ballot.

Bashir called Abyei a territory of the Misseriya, a nomadic Arab tribe who, he said, "host" the Ngok Dinka tribe. The Dinka fled Sudan's occupation but have begun returning.

"Abyei will continue as a part of Sudan and all Misseriya will participate in the Abyei referendum," Bashir said.

In late October, his press secretary denied rumours that the president was sick and said he underwent minor surgery during the holy Muslim fasting month of Ramadan, which was observed from mid-July to mid-August.

Bashir seized power in a 1989 military coup which overthrew a democratically elected government and established an Islamist regime.

He is wanted by the International Criminal Court for alleged war crimes, crimes against humanity and genocide committed in Sudan's far-western Darfur region where a rebellion began in 2003.