Mr Surapong made the appeal at a briefing to 60 ambassadors and diplomats and members of four international organisations based in Bangkok at the Foreign Affairs Ministry yesterday.
Participants included ambassadors from Australia, Spain, Belgium, the European Union, Germany and Russia. Mr Surapong also hinted at the likelihood of the Internal Security Act (ISA), now in effect in place of the decree, being revoked as well if the political violence eases.
However, if violence flares up again, the decree might be re-introduced.
He urged foreign investors who might have stayed away because of the political unrest to return.
"Thailand is still an interesting place to invest in," Mr Surapong said.
He also hoped other countries would lift negative travel advisories now the decree has been called off.
The caretaker minister said he also planned to visit China, Japan and South Korea soon to provide an update on the political situation in Thailand.
Soldiers from the three armed forces will continue to man security checkpoints in Bangkok and nearby provinces, despite the emergency decree being lifted and replaced by the ISA.
Maj Gen Warah Boonyasit, commander of the army's 1st Infantry Division, said 176 military checkpoints set up in areas previously covered by the special security law would remain unchanged.
However, some adjustments may be made to take account of the improving security situation, he said.
Media reports have indicated that the Centre for the Administration of Peace and Order (Capo) is considering cutting the number of checkpoints.
Maj Gen Warah said the military would wait for the centre's decision and is ready to respond as necessary.
Capo has been reinstated to replace the Centre for Maintaining Peace and Order.