diff --git a/src/xtd.core/src/xtd/threading/timer.cpp b/src/xtd.core/src/xtd/threading/timer.cpp
index 3eb3c22e5f6a..2ea287b9fe2b 100644
--- a/src/xtd.core/src/xtd/threading/timer.cpp
+++ b/src/xtd.core/src/xtd/threading/timer.cpp
@@ -51,7 +51,7 @@ timer::timer(const timer_callback& callback, std::any state, int32 due_time, int
 timer::timer(const timer_callback& callback, std::any state, int64 due_time, int64 period) : timer(callback, state, as<int32>(due_time), as<int32>(period)) {
 }
 
-timer::timer(const timer_callback& callback, std::any state, const time_span& due_time, const time_span& period) : timer(callback, state, due_time.total_milliseconds_duration().count(), period.total_milliseconds_duration().count()) {
+timer::timer(const timer_callback& callback, std::any state, const time_span& due_time, const time_span& period) : timer(callback, state, as<int32>(due_time.total_milliseconds_duration().count()), as<int32>(period.total_milliseconds_duration().count())) {
 }
 
 timer::timer(const timer_callback& callback, std::any state, uint32 due_time, uint32 period) : timer(callback, state, as<int32>(due_time), as<int32>(period)) {